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What is IO Genix Vitamin B Complex?
IO Genix Vitamin B Complex is a B-group vitamin complex in tablet form. One tablet brings together all eight B vitamins, plus 50 mg of inositol and 50 mg of choline bitartrate. The bottle holds 60 tablets, and the intended dose is one tablet a day: two months of use per bottle.
The B vitamins form a group of eight molecules that have little in common chemically, but that are all involved in turning nutrients into energy the cell can use. That is the historical reason for grouping them under a single letter, and it is also why they are so often sold together rather than one by one.
The tablet format changes one concrete thing compared with capsules: it makes it possible to fit ten ingredients into a single unit to swallow. On a complex of this size, a capsule would have called for two or three doses a day. The rest of the Spanish range can be browsed in our IO Genix aisle, and the other products in the category in our vitamin B aisle.
What does one Vitamin B Complex tablet contain?
| Composition | Per tablet | % NRV |
|---|---|---|
| Vitamin B3 (niacin) | 54 mg | 338% |
| Vitamin B5 (pantothenic acid) | 18 mg | 300% |
| Vitamin B6 (pyridoxine) | 6 mg | 429% |
| Vitamin B2 (riboflavin) | 4.8 mg | 343% |
| Vitamin B1 (thiamine) | 4.7 mg | 382% |
| Vitamin B9 (folic acid) | 400 µg | 200% |
| Vitamin B8 (biotin) | 100 µg | 200% |
| Vitamin B12 (cyanocobalamin) | 3 µg | 120% |
| Inositol | 50 mg | NRV not established |
| Choline bitartrate | 50 mg | NRV not established |
| Pack size | 60 tablets, i.e. 60 days at one tablet a day | |
Every dosage exceeds the nutrient reference value, and that is normal on this type of product. The B vitamins are water-soluble: whatever the body does not retain leaves in the urine, which explains the comfortable safety margin they enjoy and why manufacturers do not hesitate to go up to 300 or 400% of the reference value. That said, a high dosage does not make a supplement more effective; it simply compensates for absorption that is never complete.
All eight B vitamins carry authorised claims in Europe, and there is no reason to stray from them. The broadest concern five of them: vitamins B2, B3, B6, B9 and B12 contribute to the reduction of tiredness and fatigue, and vitamins B1, B2, B3, B5, B6, B8 and B12 contribute to normal energy-yielding metabolism. To these are added, among others, the normal functioning of the nervous system (B1, B2, B3, B6, B8, B12) and normal red blood cell formation (B6, B12).
Two ingredients in the formula call for a word of clarification. Inositol has no authorised claim in Europe: it is present, it is not banned, but nothing can be promised about it. Choline does have authorised claims, except that they are conditional on a minimum intake these 50 mg do not reach. Put another way, those two lines fill out the label more than they change the product, and it is better to know that.
One detail of form with practical consequences: vitamin B3 is supplied as nicotinamide, not as nicotinic acid. It is the form that does not bring on the well-known hot flush with facial redness that some niacins trigger at this dosage. At 54 mg, the question would arise with the other form.
Ingredients list
Anti-caking agent (magnesium stearate), vitamin B3 (nicotinamide), inositol, choline bitartrate, pantothenic acid (calcium D-pantothenate), vitamin B6 (pyridoxine hydrochloride), vitamin B2 (riboflavin), vitamin B1 (thiamine hydrochloride), vitamin B12 (cyanocobalamin), folic acid, biotin.
Information missing from the manufacturer's file: the list of allergens present in the manufacturing plant is not disclosed for this product. We will not invent it. Please refer to the packaging you receive.
How do you take Vitamin B Complex?
Dose: 1 tablet. Liquid: a large glass of water. Timing: in the morning, with breakfast. Frequency: one dose a day. Duration: a course of 2 to 3 months, which can be repeated.
Taking it with food is not a precaution of principle. A B complex taken on an empty stomach fairly often brings on passing nausea, particularly at these dosages, and a full stomach settles the problem in almost every case. It is the first thing we say to a customer who comes back telling us they cannot tolerate their B complex.
Why the morning rather than the evening? Because the B vitamins are involved in cellular energy production throughout the day, and because taking them late adds nothing. There is, on the other hand, nothing against moving the dose to lunchtime if breakfast is not something you do.
One sign worth knowing about so as not to worry needlessly: riboflavin turns the urine bright yellow. It is a commonplace phenomenon, with no pathological meaning whatsoever, and it shows up as early as the first or second tablet. It simply indicates that the excess is being eliminated, which is the normal behaviour of a water-soluble vitamin.
A course of two to three months corresponds exactly to one bottle or one and a half. This complex combines without any overlap with an omega 3, a vitamin D or a magnesium — three categories that provide no B vitamins and that cover other needs.
Who is Vitamin B Complex for, and who is it not for?
It suits an adult whose diet is irregular, someone going through a busy period, and more broadly anyone looking for a broad intake rather than an isolated vitamin. The manufacturer restricts it to adults.
Pregnant and breastfeeding women must seek medical advice before taking it, and that is not a stock phrase: vitamin B9 is a nutrient whose intake during pregnancy is monitored precisely, and it must not be improvised from a general-purpose complex. The same goes if you are on medication: several B vitamins interact with common drugs, and that question is one for your doctor or pharmacist, not a shop assistant.
A point about vegan diets, because it is the most frequent reason for buying in this aisle. The 3 µg of vitamin B12 covers 120% of the reference value, which is fine for a general intake. But B12 absorption saturates quickly at each dose, and the protocols intended for strict vegan diets rest on markedly higher dosages. If you consume no animal products at all, this tablet will probably not be enough on its own: talk it over with a healthcare professional and consider a dedicated B12.
What not to expect from it: it does not give you energy in the sense of a noticeable lift. B vitamins are not stimulants, they contain no caffeine, and you will feel nothing when you take them. They take part in the reactions that release energy from food, which is a very different thing. Nor does a B complex make up for a night's sleep.
B complex or multivitamin?
The two products look alike on the shelf and yet answer two distinct logics.
A multivitamin casts a wide net: vitamins A, C, D, E, K, the eight B vitamins, plus a series of minerals such as zinc, magnesium or selenium. The price of that breadth is that each nutrient is present at a more modest dosage, often around 100% of the reference value. It is the right choice when you do not know precisely what is lacking and you want a general-purpose base: our multivitamins aisle is there for that.
A B complex does the opposite: fewer ingredients, but dosages three to four times the reference value. It is the right choice when your aim is targeted — an unbalanced diet, a diet excluding animal products, persistent tiredness already discussed with a doctor.
And it has to be said plainly: taking both at once makes little sense, since the multivitamin already contains all eight B vitamins. Choose one or the other. If your priority is antioxidant defence rather than energy metabolism, vitamin C is what to look at, with a different logic again.
Frequently asked questions
Why do the dosages exceed 300% of the NRV?
Because the B vitamins are water-soluble: the body eliminates the excess in the urine, which gives them a wide safety margin. Manufacturers therefore raise the dosages to compensate for partial absorption. It is not a guarantee of greater effectiveness, simply common practice and safe at the levels given here.
My urine is turning bright yellow, is that normal?
Yes, entirely. It is riboflavin, vitamin B2, which is naturally an intense yellow colour. The phenomenon appears with the very first tablets, has no pathological meaning and stops when you stop taking them. It simply signals that the excess is being eliminated normally.
Is this complex enough for a vegan diet?
Not necessarily. The 3 µg of B12 covers 120% of the reference value, but absorption of this vitamin saturates at each dose and the protocols intended for strict vegans use far higher dosages. Take the advice of a healthcare professional and consider a dedicated vitamin B12.
Can it be taken at the same time as a multivitamin?
It is possible but of little use: a multivitamin already contains all eight B vitamins. You would be stacking the same nutrients with no added benefit. Choose one or the other depending on whether you are after a broad base or a targeted intake of B vitamins.
What are inositol and choline for in the formula?
Inositol has no authorised claim in Europe. Choline does have them, but they assume a minimum intake that the 50 mg present here does not reach. Those two lines round out the label without genuinely changing the product's profile, and it is more honest to say so.
Does vitamin B3 cause flushing?
No, not in this form. The tablet supplies nicotinamide, not nicotinic acid. It is the latter that triggers the sensation of heat and facial redness from a few tens of milligrams upwards. With nicotinamide, the phenomenon does not occur.
How long does a bottle last?
60 tablets at one a day: two months exactly. As the course recommended by the manufacturer is two to three months, count on one bottle for a short course and one and a half for a long one.
Where can you buy IO Genix Vitamin B Complex?
The 60-tablet bottle can be ordered from this page, and we ship throughout France and Europe. At the Vendargues shop, about ten minutes from Montpellier, it is the product we reach for when a customer is torn between eight separate bottles of B vitamins: one tablet in the morning settles the question, and the budget stays reasonable. The whole vitamin aisle can be browsed in our sports nutrition selection.
What is Now Foods Methyl B-12 5000 mcg?
Now Foods Methyl B-12 5000 mcg is a vitamin B12 supplement in tablets that dissolve under the tongue, providing 5,000 µg per tablet. The sizes listed here: 60 and 120 tablets, that is two or four months at one dose a day.
Two things set this product apart in the vitamin B aisle. The first is the form chosen: methylcobalamin, one of the coenzyme forms of B12, where most supplements on the market use cyanocobalamin, which is cheaper and more stable. The second is the addition of folate in the Quatrefolic® form, namely (6S)-5-methyltetrahydrofolate — the directly active form of folate, rather than synthetic folic acid.
The rest of the tablet is what gives it its texture and its taste: fructose, sorbitol, hydroxypropylcellulose, microcrystalline cellulose, citric acid, stearic acid and magnesium stearate of plant origin, natural flavourings. The manufacturer states a composition with no artificial preservatives, no synthetic colourings and no sweeteners. Now Foods is an American brand whose range we stock in our Now Foods aisle.
What does one tablet contain?
| Nutrient | Per tablet | % European NRV | Form supplied |
|---|---|---|---|
| Vitamin B12 | 5,000 µg | 200,000% | Methylcobalamin |
| Folate | 400 µg of (6S)-5-MTHF | 200% | Quatrefolic®, glucosamine salt |
NRVs within the meaning of Regulation 1169/2011: 2.5 µg for vitamin B12, 200 µg for folate. One labelling discrepancy deserves to be flagged rather than glossed over: the manufacturer, being American, expresses folate as 680 µg of dietary folate equivalents (DFE), a calculation convention specific to United States regulations, for an actual quantity of 400 µg of 5-MTHF. We show the actual quantity. Depending on which value is used, the European percentage would come out at 200% or at 340%: we prefer to give the more conservative figure and explain why.
Now for the number that leaps off the page. 5,000 µg is two thousand times the European reference value. That looks absurd, and it is not quite: B12 is absorbed only in very small amounts at each dose, and massive doses are the usual way of getting round that limit in people who absorb it poorly. What matters here is that this product is not a maintenance dose. For a simple top-up, a multivitamin providing 2.5 or 25 µg does the job.
On safety, two markers. EFSA has set no upper limit for vitamin B12, which is water-soluble and cleared in the urine. It does, however, set 1,000 µg a day as the limit for folic acid in adults: the 400 µg in this tablet stay below that, but if you are already taking a multivitamin or a pregnancy supplement, add it all up.
The applicable regulatory wordings are precise, and they are broad. Vitamin B12 contributes to the reduction of tiredness and fatigue, to the normal functioning of the nervous system, to normal energy-yielding metabolism, to normal red blood cell formation, to normal homocysteine metabolism, to normal psychological function and to the normal function of the immune system. Folate contributes to normal blood formation, to normal amino acid synthesis, to the reduction of tiredness and fatigue and to the growth of maternal tissue during pregnancy.
How do you take Methyl B-12?
Dose: 1 tablet. Liquid: none, the tablet dissolves under the tongue. Timing: in the morning, with a meal. Frequency: one dose a day. Duration: the manufacturer sets no course length; where status is deficient, supplementation is generally long-term and is managed with a doctor.
The instructions come down to a single sentence: place the tablet under the tongue and let it dissolve for two to three minutes rather than swallowing it straight away. The manufacturer also advises keeping it away from hot drinks. One honest clarification: we have no ANSES or EFSA source establishing that the sublingual route does better than a swallowed tablet, so we will not write that it is superior. What we can say is that the format is pleasant, naturally flavoured, and calls for no glass of water — which, on a daily dose taken over the long term, counts for more than you might think.
The morning dose is the one the manufacturer settles on. The taste is slightly sweet, the fructose and the sorbitol serving as the base: this is not an unpleasant tablet to let dissolve, unlike a good many vitamins.
One point of common sense to finish with: B12 is measured by a blood test. If you are supplementing at 5,000 µg, a blood test taken afterwards no longer means very much. Have your status checked before you start, not after.
Who is this product for, and who is it not for?
It is aimed at three specific situations, and the manufacturer names them itself. Vegetarians and vegans first: vitamin B12 is almost exclusively of animal origin, and supplementing it is not a convenience but a necessity on a vegan diet. Then older people, whose digestive absorption declines. And diagnosed deficiencies, under medical supervision.
The manufacturer asks you to consult a healthcare professional if you are pregnant, breastfeeding or on medication, and recommends medical supervision for a high dose taken over a prolonged period. That instruction should be taken seriously: this is not a product to take “just in case” for two years without ever having a check-up. The product is declared free from gluten, wheat, soya, milk, egg, fish and nuts, but made in a facility that handles other allergens.
It suits you less well if you eat meat, fish and eggs regularly: in that case there is no reason at all to take 5,000 µg, and a multivitamin already covers the requirement comfortably. It also contains sorbitol, a polyol that can upset a sensitive gut at repeated doses.
What not to expect from it. This is not an energy product. “Contributing to the reduction of tiredness and fatigue” means correcting a shortfall, not giving a lift to someone whose status is normal — the distinction is crucial, and it is the one the aisle glosses over most often. Nor is it a performance product: no sports claim exists for B12.
Methyl B-12 on its own or a multivitamin?
That is the real choice, and it depends entirely on your diet.
A multivitamin generally provides 2.5 to 25 µg of B12, among some twenty other nutrients. It is the better choice if you eat a bit of everything in an irregular way and are looking for a general safety net: one dose, one bottle, everything covered. Its drawback is that it covers nothing in depth, and its B12 content bears no comparison with this one.
Methyl B-12 does the opposite: a single nutrient, dosed very high, plus folate. It is the right choice on a vegan diet or where absorption is impaired — two situations in which a multivitamin will not be enough. If that applies to you, take the problem as a whole: a diet without animal products also calls for keeping an eye on iron and on protein intake, which our plant proteins aisle covers. And avoid the most widespread shortcut: spirulina has many merits, but it is not accepted as a reliable source of vitamin B12. Do not count on it for that.
Frequently asked questions
5,000 µg, isn't that far too much?
It is two thousand times the European reference value, and it is deliberate: B12 is absorbed only in a small proportion at each dose, which high doses make up for. EFSA has set no upper limit for this vitamin, which is water-soluble and cleared in the urine. It remains a corrective dose, not a maintenance dose.
Methylcobalamin or cyanocobalamin?
Methylcobalamin is a coenzyme form, directly usable; cyanocobalamin is a synthetic form, more stable and cheaper, which the body has to convert. The authorised regulatory wordings are identical for both, and we have no official source establishing that one is superior to the other.
What is the difference between 400 and 680 µg of folate?
None in quantity: these are two ways of describing the same thing. The tablet provides 400 µg of (6S)-5-MTHF; the figure of 680 µg corresponds to the conversion into dietary folate equivalents, an American convention. On a European label, it is the 400 µg value that should be compared.
Does it really have to dissolve under the tongue?
That is what the manufacturer asks for, two to three minutes, avoiding hot drinks just afterwards. We have no official source proving that this route does better than a swallowed tablet. The tablet is flavoured, though, and needs no water, which makes a daily dose easier to keep up.
How long does one bottle last?
Two months for the 60-tablet size, four months for the 120, at one tablet a day. The manufacturer sets no time limit: on a vegan diet, supplementation is generally permanent, and that is a point to settle with a doctor.
Can it be taken during pregnancy?
Not without medical advice: that is the manufacturer's explicit statement. Folate has a particular role during pregnancy, but pregnancy supplements already contain it, and the combined total must stay below the limit of 1,000 µg a day set by EFSA for folic acid. This question is one to settle with your doctor or your midwife.
Is the product suitable for vegans?
Yes. No ingredient of animal origin goes into the composition, the stearic acid and the magnesium stearate both being of plant origin. That is logical: vegans are precisely the primary audience for this product, vitamin B12 being almost absent from the plant kingdom.
Where can you buy Now Foods Methyl B-12 5000 mcg?
Both sizes can be ordered from this page, and we ship anywhere in France and in Europe. The 120-tablet bottle makes sense if you are settled into a vegan diet for the long term; the 60-tablet one is enough to start with.
At the Vendargues shop, about ten minutes from Montpellier, this is one of the few products where we begin by asking a medical question: have you had your B12 measured? The advice changes entirely depending on the answer, and a measurement taken after supplementation has begun is worth nothing. The rest of the aisle can be browsed in our sports nutrition section.
What is Now Foods Biotin 5000 mcg?
It is a biotin supplement in vegetable capsules, dosed at 5,000 µg per capsule. The formats listed: 60 and 120 capsules, that is two or four months at one capsule a day.
Biotin, also known as vitamin B8 or vitamin H, is a water-soluble B-group vitamin. The formula is about as simple as a supplement can be: biotin, rice flour as a carrier, a hypromellose capsule, stearic acid of vegetable origin and silicon dioxide.
As the capsule is plant-based, the product is suitable for vegetarians. The manufacturer declares it free from wheat, gluten, soya, milk, egg, fish, shellfish, nuts, sesame and GMOs. The rest of the American range is in our Now Foods section, and the whole category in vitamin B.
What does one capsule contain?
| Nutrient | Per capsule | NRV | % NRV |
|---|---|---|---|
| Biotin (vitamin B8) | 5,000 µg | 50 µg | 10,000% |
Other ingredients: rice flour, hypromellose (vegetable capsule), stearic acid of vegetable origin, silicon dioxide. NRV within the meaning of Regulation 1169/2011: 50 µg. Pack sizes: 60 or 120 vegetable capsules.
One hundred times the reference value deserves a frank explanation. Biotin is water-soluble: whatever the body does not use leaves in the urine, and EFSA has set no upper limit for this vitamin. The 5,000 µg dose is the American market standard on hair products; it is not dangerous, but nothing shows that it does better than a 50 or 150 µg dose in a person whose status is normal. We would rather say so.
Let us come to what the regulations authorise, because it is the most useful point on this page. Biotin contributes to the maintenance of normal hair, normal skin and normal mucous membranes, to normal energy-yielding metabolism, to normal macronutrient metabolism, to the normal functioning of the nervous system and to normal psychological function. Those are the exact wordings, and they are broad.
On the other hand, and this is a distinction the whole aisle glosses over: there is no authorised claim concerning nails for biotin. European regulation recognises hair, skin and mucous membranes — not nails. You will read the opposite just about everywhere; that is nonetheless how it stands. A second distinction, just as important: “contributing to the maintenance of normal hair” means avoiding the consequences of a shortfall, not growing the hair of someone whose status is already fine. Biotin deficiency is rare on an ordinary diet.
How should you take biotin?
Dose: 1 capsule. Liquid: a glass of water. When: with a meal, preferably breakfast or lunch. Frequency: one intake a day. Duration: at least 3 months without a break; the manufacturer indicates that the effects generally show after 6 to 8 weeks.
The timescale is the most important thing to take on board here, and it is in no way a sales argument: hair grows about one centimetre a month. Whatever you take, no visible change is possible before several weeks, and judging after a fortnight makes no sense. That is precisely why the 120-capsule format makes more sense than the 60.
Taking it with a meal is advised for digestive comfort more than for absorption, biotin being water-soluble. The real challenge is consistency: pair the capsule with a fixed daily habit, it is the only way to keep going for three months without forgetting.
One pairing that makes sense: zinc also has an authorised wording on the maintenance of normal hair, and vitamin C one on normal collagen formation. If your concern is hair, those three complement one another better than biotin alone pushed to a hundred times the NRV.
Who is this product for, and who is it not for?
It is for adults only and suitable for vegetarians, the capsule being plant-based and the excipients of vegetable origin. Its “free from” list is one of the shortest in the aisle, which makes it a simple option for allergy-prone profiles.
One warning deserves reading twice, because it can have real consequences. High-dose biotin interferes with certain blood tests — thyroid and troponin assays are the most affected — and can skew a result in either direction. Always tell your doctor or the laboratory that you are taking biotin before any blood test. This is not a token precaution: it is the no. 1 reason why this dose has to be flagged.
The manufacturer also asks you to consult a healthcare professional in case of pregnancy, breastfeeding, medical treatment or a health problem. The product is made in a facility that handles other allergenic ingredients.
It is less suitable if you already take a multivitamin or a hair complex: most already contain some, and stacking achieves nothing while making the blood test problem worse.
What you should not expect of it, and we will be direct: biotin does not regrow hair. If your hair loss is recent, heavy or localised, it is a matter for a doctor — iron deficiency, a thyroid disorder or androgenetic alopecia are not treated with a vitamin. Nor is there any claim concerning nails.
Biotin or collagen?
These are the two products most often compared in this aisle, and they do not play the same role at all.
A collagen supplies peptides in bulk quantities — 5 to 20 g per dose — and is taken as a powder. It should be said that, just like biotin on nails, collagen has no authorised health claim in Europe. What can be said about it rests on its composition, not on an effect. It is the choice of those who prefer a massive protein intake to a dosed vitamin, and who accept a powder to mix rather than a capsule.
Biotin wins on a point that is not a small one: it, for its part, does have an authorised wording on the maintenance of normal hair and normal skin. It is the only one of the two whose role the regulations recognise. It is also simpler: one capsule a day, no taste, no preparation, and a bottle of 120 lasts four months.
The advice we give most often: if you are to take only one thing, take the biotin — provided you expect no miracle from it — and add zinc if your diet is short of it. If you want broad cover without multiplying bottles, a multivitamin already contains both, at more moderate and amply sufficient doses.
Frequently asked questions
5,000 µg, isn't that excessive?
It is one hundred times the reference value of 50 µg. Biotin being water-soluble, the excess is eliminated in the urine, and EFSA has set no upper limit. So it is not dangerous, but nothing shows that such a dose does better than a moderate intake in a person whose status is normal.
Does biotin act on the nails?
No claim concerning nails is authorised in Europe for biotin. The permitted wordings cover hair, skin and mucous membranes. You will read the opposite on many packs and websites: that changes nothing about the regulatory framework, and we will not write what is not authorised.
Should you tell your doctor before a blood test?
Yes, every time, and it is the most important point on this page. High-dose biotin interferes with certain blood assays, particularly those for thyroid and troponin, and can skew a result. Always report this supplementation to the laboratory or to your doctor.
How long before you see anything?
The manufacturer speaks of 6 to 8 weeks and advises at least three months without a break. That fits the biology: hair grows about one centimetre a month, and nothing visible can appear sooner. A judgement made after a fortnight is worth nothing.
Are the capsules suitable for vegans?
The shell is hypromellose, of vegetable origin, and the stearic acid is likewise vegetable. The manufacturer describes the product as vegetarian; the biotin in supplements being generally produced synthetically, the formula contains no animal ingredient identified in the data supplied.
Can it be combined with a multivitamin?
Technically yes, but there is little point: most multivitamins already contain 50 to 200 µg of biotin, and stacking adds nothing more. It does, however, make the interference with blood tests worse. Check the label of what you already take before adding this bottle.
How long does a bottle last?
Two months for the 60-capsule format, four months for the 120, at one capsule a day. As the manufacturer recommends at least three months without a break, the 120 format is the most coherent: it covers the advised duration without a gap.
Where to buy Now Foods Biotin 5000 mcg?
The formats can be ordered from this page, and we ship throughout France and Europe. If you are starting out, go straight for the 120 capsules: three months is the minimum for judging anything at all.
At the Vendargues shop, about ten minutes from Montpellier, this is the aisle where we most often put a product back on its shelf. When hair loss is recent or marked, our answer has always been the same: go and see a doctor before buying a vitamin. And if you are taking biotin, remember to say so at the laboratory before your next blood test.
What is IO Genix Vitamin B12 1000 µg ER?
IO Genix Vitamin B12 1000 µg ER is a coated tablet of vitamin B12 in the form of cyanocobalamin. One tablet provides 1,000 µg, which is 40,000% of the nutrient reference value. The bottle holds 90 of them, which comes to three months at one tablet a day.
The two letters “ER” stand for extended release, prolonged release. The tablet does not release its dose into the stomach all at once: it diffuses it gradually, which the hydroxypropyl methylcellulose used as a thickener in the body of the tablet makes possible. It is the only thing that sets this product apart from a conventional B12, and it determines how it should be taken.
Vitamin B12 is the only nutrient the body can neither make nor find in the plant kingdom. It comes exclusively from foods of animal origin — meat, fish, eggs, dairy products — because it is synthesised by bacteria. That is what makes it the baseline supplement for vegan diets, and one of the few whose necessity is not up for debate in that particular case. The rest of the Spanish range can be browsed in our IO Genix aisle, and the other products in the category in our vitamin B aisle.
What does one Vitamin B12 ER tablet contain?
| Composition | Per tablet | % NRV |
|---|---|---|
| Vitamin B12 (cyanocobalamin) | 1,000 µg | 40,000% |
| Serving | 1 tablet a day | |
| Pack size | 90 tablets, i.e. three months of use | |
40,000% of the reference value is a figure that makes you sit up, and it deserves a full explanation rather than a shrug. Oral absorption of vitamin B12 is limited in two ways. The active route, which goes through the intrinsic factor produced in the stomach, saturates at around 1 to 2 µg per dose, and no more. Beyond that, all that is left is passive diffusion across the intestinal wall, whose yield is of the order of 1%. In other words, a lot has to be offered for a little to get through.
That is the whole logic of the 1,000 µg dose: it is not commercial one-upmanship, it is the arithmetical consequence of a saturable absorption mechanism. And it is also why extended release makes sense here: by spreading out when the vitamin becomes available, it calls on the active route several times over rather than just once.
Vitamin B12 carries several authorised claims in Europe, and they are more than enough to describe what it is for. Vitamin B12 contributes to the reduction of tiredness and fatigue, contributes to normal functioning of the nervous system, contributes to normal red blood cell formation, contributes to normal energy-yielding metabolism, contributes to normal homocysteine metabolism, contributes to the normal function of the immune system and has a role in the process of cell division. These are the official wordings.
The form used is cyanocobalamin. It is the most stable of the B12 forms, the one that best withstands heat and light, and by far the most studied. The body has to convert it into active forms, a conversion that takes place normally in a healthy person. The manufacturer also states that the product is free from gelatine, gluten, lactose and GMOs.
Information missing from the manufacturer's file: the exact period over which the release is spread is not disclosed. We will not invent it and we stick to the principle: the diffusion is gradual, not immediate.
Ingredients list
Bulking agents (microcrystalline cellulose, calcium carbonate), thickener (hydroxypropyl methylcellulose), anti-caking agents (silicon dioxide, magnesium stearate), coating agent (clear HPMC powder), cyanocobalamin (vitamin B12).
May contain traces of TREE NUTS, PEANUTS, EGGS, MILK, SULPHITES, FISH and SOYA. Free from GMOs, gluten, gelatine, artificial colourings, starch, lactose, salt and added sugar.
How do you take Vitamin B12 ER?
Dose: 1 tablet, to be swallowed whole. Liquid: a glass of water. Timing: any time of day, preferably with a meal. Frequency: one dose a day. Duration: the manufacturer sets no time limit; supplementation is ongoing for as long as the reason behind it persists.
The most important instruction on this page comes down to three words: do not crunch. Do not chew it, crush it or cut the tablet in half either. Extended release depends entirely on the tablet staying intact; breaking it releases the whole dose at once and does away with the only advantage you are paying for. If you find tablets hard to swallow, take it in the middle of a mouthful of fruit purée or yoghurt, without breaking it up.
Two interactions are worth noting, because they are common and easy to avoid. A high dose of vitamin C, above 500 mg, taken in the hour before or after, reduces the absorption of B12: space the two doses out. And several common medicines — metformin, proton pump inhibitors such as omeprazole, H2 blockers, colchicine — reduce the absorption of vitamin B12. The manufacturer recommends leaving two to three hours between them. If this applies to you, speak to your doctor or pharmacist.
When will you notice anything? If your levels are normal, you will feel nothing at all, and that is entirely to be expected: B12 is not a stimulant. It combines without any overlap with an omega 3 or a spirulina, the latter not in fact being a reliable source of B12, whatever you may often read.
Who is Vitamin B12 ER for, and who is it not for?
It is aimed first and foremost at people whose diet provides no B12, or very little: vegan and strict vegetarian diets, above all. It also concerns people over sixty, in whom falling stomach acidity reduces the extraction of B12 from food, and those taking a medicine known to hinder its absorption over the long term.
It is not suitable in cases of allergy to cobalt or cobalamin — the B12 molecule is built around a cobalt atom. The manufacturer also flags Leber's disease, a hereditary optic neuropathy for which cyanocobalamin is contraindicated. It is a rare condition, but the warning is explicit on the packaging and we reproduce it as it stands.
In cases of absorption disorders — Crohn's disease, colitis, gastrectomy, pancreatic insufficiency — or diagnosed pernicious anaemia, the oral route may not be enough and follow-up is a matter for a doctor, not a supplement bought online. For pregnant and breastfeeding women, B12 requirements are higher, but what to do about it is decided with a healthcare professional.
What not to expect from it: it is no substitute for a diagnosis. Persistent tiredness can have ten causes, and only a blood test will say whether B12 is one of them. If you belong to an at-risk group, have your B12 measured rather than assuming — it is quicker, more reliable, and it avoids supplementing beside the real issue.
Extended-release tablet or B vitamin complex?
The question comes up every time, and the answer depends entirely on why you are buying.
A B vitamin complex provides all eight vitamins in the group, with B12 dosages that generally hover around a few micrograms — enough to cover the reference value, not to make up for a complete absence of dietary intake. It is the right choice if your diet is simply irregular and you are looking for a broad safety net. Our multivitamins aisle answers the same logic, on an even broader scale.
This tablet does the opposite: a single vitamin, at 1,000 µg, with release spread over time. It is the format that fits when B12 is precisely the nutrient that is lacking, that is to say on a diet excluding all animal products, or when a medicine hinders its absorption. In that case, a general-purpose B complex would be undersized.
There is a third situation, often overlooked: B12 works hand in hand with vitamin B9 and with iron in red blood cell formation. If you follow a vegan diet, these three nutrients deserve to be looked at together, with the help of a healthcare professional. The plant proteins aisle rounds out the same approach on the protein side.
Frequently asked questions
Why 1,000 µg when the reference value is 2.5 µg?
Because oral absorption of B12 saturates: the active route tops out at around 1 to 2 µg per dose, and beyond that only passive diffusion operates, with a yield of about 1%. A high dosage compensates for that low yield. It is not one-upmanship, it is arithmetic.
Can the tablet be cut or crunched?
No, never. It is the one absolute rule with this product. Crunching, chewing or crushing the tablet releases the whole dose instantly and cancels out the extended release. If the tablet goes down badly, swallow it with a spoonful of yoghurt or fruit purée, but whole.
Cyanocobalamin or methylcobalamin?
Cyanocobalamin is more stable, better documented and less expensive; the body converts it into active forms without difficulty in a healthy person. Methylcobalamin is already active but more fragile in storage. For everyday use, the form chosen here is a defensible one.
Is this tablet suitable for vegans?
The manufacturer states that it is free from gelatine, gluten, lactose and GMOs, and cyanocobalamin is obtained by bacterial fermentation. Nothing in the ingredients list is of animal origin. Do note, however, the possible traces of eggs, milk and fish linked to the manufacturing plant.
Should vitamin C be avoided at the same time?
Yes, if the dose exceeds 500 mg. The manufacturer asks that you leave at least an hour between them, because a high dose of vitamin C taken at the same time reduces the absorption of B12. If you take a 1,000 mg vitamin C in the morning, move the B12 to lunchtime.
How long before an effect is felt?
None at all if your levels are normal: B12 is not a stimulant and produces no sensation. Where a deficiency has been confirmed by a blood test, an improvement in tiredness is generally seen over several weeks of oral supplementation, and follow-up belongs to the doctor who made the diagnosis.
How long does a bottle last?
90 tablets at one a day: three months. As B12 supplementation is designed for the long run on a vegan diet, it is a pack size suited to ongoing use rather than to a one-off course.
Where can you buy IO Genix Vitamin B12 ER?
The 90-tablet bottle can be ordered from this page, and we ship throughout France and Europe. At the Vendargues shop, about ten minutes from Montpellier, it is the first supplement we recommend to a customer who tells us they have gone vegan: before the proteins, before the omega 3, comes B12, because it is the only intake that no plant food supplies reliably. The rest of our selection can be browsed in the sports nutrition aisle.
Qu'est-ce que la Vitamine B12 liposomale d'Osavi ?
C'est la vitamine B12 d'Osavi en version liposomale. Une gélule végétale apporte 100 µg de vitamine B12 sous forme de méthylcobalamine, encapsulée dans des liposomes — la matière première Liposovit®-B12.
Deux points d'étiquette méritent l'attention. Le premier est la forme : la méthylcobalamine est la forme méthylée de la vitamine, directement active, là où beaucoup de produits emploient de la cyanocobalamine. Le second est l'encapsulation liposomale.
La vitamine B12 contribue au fonctionnement normal du système nerveux, à des fonctions psychologiques normales, à la réduction de la fatigue, à un métabolisme énergétique normal, au métabolisme normal de l'homocystéine, à la formation normale de globules rouges et au fonctionnement normal du système immunitaire.
Qu'apporte la forme liposomale ?
Un liposome est une vésicule construite avec les mêmes matériaux que les membranes de nos cellules : des phospholipides, ici issus de la lécithine de tournesol. L'actif y est enfermé plutôt que simplement mélangé à une poudre.
Osavi emploie une technologie liposomale sèche, ce qui permet de présenter le produit en gélule plutôt qu'en flacon liquide : plus simple à doser, à transporter, et sans goût.
Le contrôle, argument central de la marque
C'est ce qui nous a décidés à référencer Osavi. Chaque lot de production part dans un laboratoire indépendant — J.S. Hamilton ou GBA — qui vérifie trois choses : la teneur réelle en substances déclarées à l'étiquette, l'absence de métaux lourds et la pureté microbiologique. Un certificat d'analyse est publié pour chaque produit ; c'est le sens du logo « Lab Tested » sur le flacon.
Les procédés de production sont certifiés ISO 9001:2015 et ISO 22000:2018.
À qui s'adresse-t-elle ?
La vitamine B12 se trouve presque exclusivement dans les produits animaux. C'est donc le complément de référence pour les personnes qui suivent une alimentation végétalienne ou largement végétarienne, et la gélule est elle-même végétale.
Questions fréquentes
Méthylcobalamine ou cyanocobalamine ?
La méthylcobalamine est la forme méthylée, directement utilisable par l'organisme ; la cyanocobalamine doit être convertie. C'est la forme employée ici, et c'est écrit sur l'étiquette.
Convient-elle à une alimentation végétalienne ?
Oui : la gélule est végétale et les ingrédients le sont également. C'est l'usage principal de ce type de produit, la B12 étant quasi absente des sources végétales.
Qu'est-ce que le Liposovit®-B12 ?
La matière première liposomale d'Osavi : la méthylcobalamine est encapsulée dans des liposomes de phospholipides de lécithine de tournesol, avec de la maltodextrine et du glycérol comme support.
Que signifie « Lab Tested » sur le flacon ?
Que le lot a été analysé par un laboratoire indépendant — J.S. Hamilton ou GBA — sur sa composition, les métaux lourds et la pureté microbiologique, et qu'un certificat d'analyse est publié pour le produit. C'est la marque de fabrique d'Osavi.
Où acheter la Vitamine B12 liposomale Osavi ?
Vous pouvez le commander sur cette page, et nous expédions partout en France et en Europe. Toute la gamme est sur notre page Osavi, et notre rayon vitamines B permet de comparer les étiquettes.
Qu'est-ce que le Niacinamide d'Osavi ?
C'est la vitamine B3 d'Osavi, sous forme de nicotinamide. Une gélule végétale apporte 500 mg de nicotinamide, dans une formule à trois ingrédients : nicotinamide, enveloppe de la gélule et inuline.
La niacine contribue au fonctionnement normal du système nerveux, à des fonctions psychologiques normales, à la réduction de la fatigue, au maintien de muqueuses et d'une peau normales, et à un métabolisme énergétique normal.
Pourquoi cette marque plutôt qu'une autre
Sur un rayon où tout le monde écrit « haute qualité », Osavi accepte de se faire contredire par un document. Chaque lot est analysé par un laboratoire extérieur, J.S. Hamilton ou GBA, sur la teneur en substances déclarées, les métaux lourds et la pureté microbiologique — et le certificat d'analyse est publié. Le logo « Lab Tested » de l'étiquette renvoie à ce contrôle.
S'y ajoutent des procédés certifiés ISO 9001:2015 et ISO 22000:2018, et une liste d'ingrédients volontairement courte : pas d'arôme de synthèse, pas de colorant, pas de charge inutile.
Questions fréquentes
Quelle est la différence entre niacinamide et niacine ?
Le niacinamide, ou nicotinamide, est l'une des deux formes de la vitamine B3 ; l'autre est l'acide nicotinique. Toutes deux apportent de la vitamine B3, mais seul l'acide nicotinique provoque le flush, cette rougeur passagère.
Le niacinamide provoque-t-il le flush ?
Non, c'est précisément son intérêt. Le flush est propre à l'acide nicotinique.
La gélule est-elle végétale ?
Oui, l'enveloppe est en hydroxypropylméthylcellulose ; les deux autres ingrédients sont le nicotinamide et l'inuline.
Que signifie « Lab Tested » sur le flacon ?
Que le lot a été analysé par un laboratoire indépendant — J.S. Hamilton ou GBA — sur sa composition, les métaux lourds et la pureté microbiologique, et qu'un certificat d'analyse est publié pour le produit. C'est la marque de fabrique d'Osavi.
Où acheter le Niacinamide Osavi ?
Vous pouvez le commander sur cette page, et nous expédions partout en France et en Europe. Toute la gamme est sur notre page Osavi, et notre rayon vitamines B permet de comparer les étiquettes.
Qu'est-ce que la Vitamine B5 d'Osavi ?
C'est l'acide pantothénique d'Osavi, sous forme de D-pantothénate de calcium. Une gélule végétale apporte 200 mg, dans une formule à trois ingrédients.
L'acide pantothénique contribue à des performances intellectuelles normales, à la réduction de la fatigue, à un métabolisme énergétique normal, et à la synthèse et au métabolisme normaux des hormones stéroïdiennes, de la vitamine D et de certains neurotransmetteurs.
Un dosage franc sur une vitamine discrète
La B5 est l'une des vitamines du groupe B dont on parle le moins, parce qu'elle est largement présente dans l'alimentation — son nom vient du grec pantothen, « de partout ». Les produits qui en proposent une dose élevée et isolée sont peu nombreux : la plupart du temps, elle n'apparaît qu'en complément d'un complexe B.
Si vous cherchez un apport de B5 à part entière plutôt qu'une ligne dans un multivitamines, c'est ce que fait cette référence. Notre rayon vitamines B regroupe les autres approches, complexes inclus.
Questions fréquentes
Combien de B5 par gélule ?
200 mg d'acide pantothénique sous forme de D-pantothénate de calcium. Une gélule par jour selon l'indication du fabricant.
Qu'est-ce que le D-pantothénate de calcium ?
La forme sous laquelle l'acide pantothénique est couramment apporté dans les compléments : un sel de calcium de la vitamine, stable et bien documenté.
Pourquoi la prendre le matin ?
C'est l'indication du fabricant. Comme pour toutes les vitamines du groupe B, hydrosolubles, la prise du matin est l'habitude la plus courante — l'essentiel reste la régularité.
Faut-il la prendre seule ou dans un complexe B ?
Les deux se justifient. Un complexe couvre l'ensemble du groupe à doses modérées ; une B5 isolée permet un apport ciblé et plus élevé. C'est votre besoin qui tranche.
La gélule est-elle végétale ?
Oui, l'enveloppe est en hydroxypropylméthylcellulose. Les autres ingrédients sont le D-pantothénate de calcium et l'inuline.
Que signifie « Lab Tested » sur le flacon ?
Que le lot a été analysé par un laboratoire indépendant — J.S. Hamilton ou GBA — sur sa composition, les métaux lourds et la pureté microbiologique, et qu'un certificat d'analyse est publié pour le produit. C'est la marque de fabrique d'Osavi.
Où acheter la Vitamine B5 Osavi ?
Vous pouvez le commander sur cette page, et nous expédions partout en France et en Europe. Toute la gamme est sur notre page Osavi, et notre rayon vitamines B permet de comparer les étiquettes.
Qu'est-ce que le Méthylfolate & Méthyl-B12 d'Osavi ?
C'est un trio de vitamines B à formes méthylées, dans une gélule végétale : méthylfolate sous licence Quatrefolic®, méthylcobalamine (vitamine B12) et pyridoxal-5'-phosphate (vitamine B6).
Pourquoi des formes méthylées ?
C'est tout l'intérêt de cette référence, et ça se lit sur l'étiquette.
Les vitamines B6, B9 et B12 doivent être converties par l'organisme avant d'être utilisées. Les formes employées ici sont déjà converties : le méthylfolate plutôt que l'acide folique, la méthylcobalamine plutôt que la cyanocobalamine, le P-5-P plutôt que la pyridoxine.
Le méthylfolate est ici du Quatrefolic®, une matière première sous licence nommée sur le flacon — c'est-à-dire une information vérifiable, plutôt qu'un simple « folate ».
Notre rayon vitamines B regroupe les autres approches, complexes compris.
Questions fréquentes
Qu'apporte une gélule ?
Trois vitamines B sous formes méthylées : du méthylfolate Quatrefolic®, de la méthylcobalamine (B12) et du pyridoxal-5'-phosphate (B6). Les teneurs figurent sur l'étiquette du flacon.
Méthylfolate ou acide folique ?
Le méthylfolate est la forme active des folates, directement utilisable ; l'acide folique doit être converti par l'organisme. C'est la forme méthylée qui est employée ici.
Qu'est-ce que le Quatrefolic® ?
Une matière première sous licence pour le méthylfolate, nommée sur l'étiquette. L'intérêt d'un ingrédient breveté écrit noir sur blanc est de savoir précisément quelle forme a été utilisée.
Qu'est-ce que le P-5-P ?
Le pyridoxal-5'-phosphate, la forme active de la vitamine B6, par opposition au chlorhydrate de pyridoxine qui doit être converti.
À qui s'adresse ce produit ?
À qui cherche un apport ciblé en B6, B9 et B12 sous formes actives plutôt qu'un complexe B complet. Si vous suivez un traitement ou si vous vous interrogez sur une carence, c'est votre médecin qui tranche.
La gélule est-elle végétale ?
Oui, l'enveloppe est en hydroxypropylméthylcellulose.
Que signifie « Lab Tested » sur le flacon ?
Que le lot a été analysé par un laboratoire indépendant — J.S. Hamilton ou GBA — sur sa composition, les métaux lourds et la pureté microbiologique, et qu'un certificat d'analyse est publié pour le produit. C'est la marque de fabrique d'Osavi.
Où acheter le Méthylfolate & Méthyl-B12 Osavi ?
Vous pouvez le commander sur cette page, et nous expédions partout en France et en Europe. Toute la gamme est sur notre page Osavi, et notre rayon vitamines B permet de comparer les étiquettes.
What do the eight B vitamins do?
"Vitamin B" does not exist in the singular. The B group brings together eight distinct vitamins, unrelated chemically, united by a common history: it was believed that a single water-soluble factor had been isolated before it was understood that it contained several. They share two practical properties: water-soluble, thus poorly stored and eliminated through urine, they almost all act as coenzymes in energy production.
Each carries its own European-authorized health claims, with wording regulated to the word, usable as soon as the product is a "source of" the vitamin concerned, meaning 15% of its nutritional reference value per serving.
- B1, thiamine (NRV 1.1 mg) — coenzyme in carbohydrate metabolism. "Thiamine contributes to normal energy-yielding metabolism."
- B2, riboflavin (NRV 1.4 mg) — FAD precursor, electron carrier. "Riboflavin contributes to normal iron metabolism."
- B3, niacin (NRV 16 mg) — NAD precursor, present in hundreds of reactions. "Niacin contributes to the reduction of tiredness and fatigue."
- B5, pantothenic acid (NRV 6 mg) — component of coenzyme A. "Pantothenic acid contributes to normal mental performance."
- B6, pyridoxine (NRV 1.4 mg) — coenzyme in amino acid metabolism. "Vitamin B6 contributes to normal protein and glycogen metabolism."
- B8, biotin (NRV 50 µg) — coenzyme of carboxylases. "Biotin contributes to the maintenance of normal hair."
- B9, folate (NRV 200 µg) — one-carbon group transfer, DNA synthesis. "Folate has a role in the process of cell division."
- B12, cobalamin (NRV 2.5 µg) — coenzyme for only two, but critical, reactions. "Vitamin B12 contributes to normal red blood cell formation."
Six of them — B2, B3, B5, B6, B9, and B12 — also carry the claim "contributes to the reduction of tiredness and fatigue." It means what it says: a contribution, for those who are deficient. It does not make a B complex a stimulant.
Why are they sold as a complex rather than individually?
Three reasons, only two of which are good.
Biochemistry first: these vitamins work in series on the same pathways. Pyruvate from carbohydrates needs B1, B2, B3, and B5 to be oxidized; homocysteine metabolism jointly mobilizes B6, B9, and B12. Providing one without the others only makes sense if a precise point is targeted.
Food sources then: they largely overlap. Offal, meats, eggs, dairy products, legumes, whole grains, green vegetables, and yeasts cover the group fairly homogeneously. A diet poor in one B vitamin is often poor in several — the major exception being B12.
The third reason is commercial: a complex sells better than a single capsule. A "B complex" at 500 or 1000% of NRVs offers nothing more than a reasonable dosage if your intake is adequate, as the excess water-soluble portion is excreted in the urine. The useful benchmark is not the percentage but the adequacy with what you are already taking: many multivitamins cover the entire B group, and combining the two is wasteful.
Why is B12 not optional in a vegan diet?
This is the only case in this entire catalog where we state that supplementation is necessary and not merely useful.
B12 is synthesized only by bacteria. It is found in animal products because these bacteria live in the digestive tract of ruminants, or because the animal has consumed it. No plant contains it in an active form: neither legumes, grains, vegetables, nor any fruit. A strict vegan diet therefore ultimately leads to zero intake.
Two misleading ideas circulate. Spirulina and several algae show "B12" contents that mainly correspond to inactive analogues: these molecules resemble B12 without having its activity and can occupy the same transporters. Spirulina is interesting for other reasons, but it is not a source of B12. Plant proteins, unenriched nutritional yeast, and fermented foods are also not reliable sources.
Key implementation point: B12 absorption is saturable. Active transport, which depends on intrinsic factor secreted by the stomach, only handles a very small amount per intake; the rest only passes through passive diffusion, at about 1% of the dose. Hence, supplements are dosed well above the NRV of 2.5 µg, and weekly high-dose intake is common. The precise regimen—dose, frequency, biological control—should be decided with a doctor.
Methylcobalamin, methylfolate, P5P: Are active forms worth their price?
The commercial argument is always the same: the form sold would be "already active," hence superior to what the body must convert. What can be said honestly:
Methylcobalamin versus cyanocobalamin. Cyanocobalamin is the most stable and well-documented; the body detaches the cyanide group from it, in negligible quantity, and converts it into active forms—including methylcobalamin. The latter is perfectly valid but less stable to light, and no European claim distinguishes it: both carry the same wording.
Methylfolate versus folic acid. Same logic: 5-methyltetrahydrofolate is the circulating form; folic acid must be reduced then methylated, a conversion that MTHFR gene variants slow down in a portion of the population. Methylfolate is a good choice, but folic acid carries most of the available data.
P5P versus pyridoxine. Pyridoxal 5-phosphate (P5P) is the coenzymatic form of B6. A rarely mentioned detail: ingested P5P is in any case dephosphorylated in the intestine before being absorbed, then rephosphorylated in the liver. The theoretical advantage is therefore thinner than advertised, except in specific situations requiring a doctor's advice.
Active forms are therefore not an empty argument, but neither are they the revolution that the price suggests: they do not render classic forms ineffective.
What dose, and what are the safety limits?
Water solubility reassuringly misleads. Three B vitamins have a European upper safety limit, and these are precisely the ones often overdosed in high-percentage complexes.
Vitamin B6 is the most monitored: the European safety limit has been revised downwards and is set at 12 mg per day for adults, from all sources combined. High and prolonged intake of B6 is associated with peripheral nerve damage. However, many B complexes display 25 mg or 50 mg of B6 without any justification — and ZMA formulas also contain it.
Niacin comes in two forms: nicotinic acid, whose limit is very low due to the flushing it causes, and nicotinamide, which is much better tolerated and by far the most commonly used. The mention of the form on the label is therefore important.
Folic acid has a limit set at 1,000 µg per day for adults. High intake can mask a B12 deficiency biologically, which is a serious reason not to stack sources.
Medical advice is essential before any supplementation during pregnancy or breastfeeding — recommendations on folate around conception are precise and fall under the purview of a healthcare professional — for children and adolescents, in cases of kidney failure, during long-term treatment, or in cases of chronic illness.
Frequently Asked Questions
What are B vitamins?
Eight distinct vitamins, chemically unrelated, grouped under the same letter by historical accident: it was long believed that a single water-soluble factor had been isolated before it was discovered that it contained several, hence the gapped numbering we know — B1, B2, B3, B5, B6, B8, B9, B12. They have only two things in common. They are water-soluble, therefore poorly stored and eliminated through urine, requiring regular intake. And almost all act as coenzymes: they provide no energy themselves; they enable enzymes to extract energy from food. This is why a B complex is not a stimulant.
What is the role of B vitamins?
Three main roles, distributed differently depending on the vitamin. First, energy metabolism: B1, B2, B3, and B5 enable the oxidation of carbohydrates, fats, and proteins to produce ATP. Second, DNA synthesis and repair, carried out by folates (B9) and B12, which explains their importance in cell division and red blood cell formation. Finally, the functioning of the nervous system, where B6 is involved in the production of several neurotransmitters and B12 in the maintenance of the myelin sheath. Additionally, B6 plays a role in protein metabolism, particularly stressed in athletes with high protein intake.
How to take a B vitamin complex?
Once a day, with a meal and preferably in the morning or at noon. Taking it with a meal reduces nausea that some formulas cause on an empty stomach; taking it in the morning avoids sleep disturbances reported by some people with highly dosed complexes. Three practical points are more important than the timing. Add up your sources: if you already take a multivitamin or ZMA, a B complex is redundant and increases B6 intake. Check the B6 dose, the only truly sensitive line of a complex. And don't rely on percentages: 1000% of NRVs doesn't make it ten times better, the excess water-soluble portion is excreted in the urine.
Why does urine become bright yellow?
It's riboflavin, vitamin B2: a fluorescent yellow pigment, hence its old name lactoflavin. The unused excess is filtered by the kidneys and colors the urine within a few hours. The phenomenon is harmless and does not indicate a problem or good assimilation: it signals that the dose exceeded what your body could use. Persistent discoloration without supplement intake, however, should be reported to a doctor.
What are the symptoms of a B vitamin deficiency?
First, it must be said why the question is poorly phrased: the eight B vitamins have different roles, and a lack of B1 is not like a lack of B12. Furthermore, proven deficiencies have become rare in France, except in specific situations — vegan diet without supplementation, chronic alcoholism, malabsorption, digestive surgery, malnutrition. The manifestations described in medical literature are severe and specific: anemia and neurological disorders for B12 and folate, nerve damage for B1, skin and mucous membrane lesions for B2 and B3. Vague symptoms often invoked online — fatigue, low mood, dull hair — do not allow for any conclusions: they are shared with dozens of other situations. Doubt is raised by a blood test prescribed by a doctor, not by a purchase.
In which foods are B vitamins found?
Offal and liver cover almost the entire group. Then come meats, fish, eggs and dairy products for B2, B3, B6 and B12; legumes, whole grains and seeds for B1, B6 and B9; leafy green vegetables for folate, whose name comes from the Latin folium, the leaf; brewer's yeast for the entire group except B12.
Which fruit is richest in vitamin B12?
None, and that's the complete answer: B12 is bacterial in origin and is not present in any fruit or vegetable. The richest foods are liver, offal, shellfish and fish, then meat, eggs, and dairy products. For folate (B9), however, citrus fruits, leafy green vegetables, and legumes are good sources.
What are the reasons for a vitamin B12 deficiency?
Two very different mechanisms, which do not call for the same response. The first is insufficient intake: a vegan diet without supplementation, or a diet very low in animal products — this is the only situation where an over-the-counter supplement directly addresses the problem. The second is defective absorption, and it is medical: B12 needs gastric acid to be released from food proteins, then intrinsic factor secreted by the stomach to be absorbed in the ileum. Anything that disrupts this chain causes it to drop: age, which reduces gastric secretion, certain long-term treatments, stomach or intestinal surgeries, inflammatory bowel diseases, and pernicious anemia. In this second case, increasing dietary intake does not solve anything: a blood test and a doctor are needed.
How to detect a vitamin B12 deficiency?
By a blood test prescribed and interpreted by a doctor, and by nothing else. Serum B12 levels are the first test, but they are imperfect: a "borderline" level has no clear meaning, and the doctor may request additional markers — homocysteine, methylmalonic acid — as well as a blood count. Two pitfalls are worth knowing. A high intake of folic acid can correct anemia while allowing neurological damage to progress, which masks the problem. And starting to supplement before testing skews the result: if you suspect a deficiency, get tested first. No symptom, no self-test, and no web page can replace this approach.
How to raise B12 levels?
This question is for a doctor, not a dietary supplement: depending on the cause, high-dose oral and injectable routes do not have the same place, and biological monitoring is part of the treatment. A general public supplement ensures intake for a healthy person; it does not correct a diagnosed anomaly.
How long does a course of B vitamins last?
One to three months is the common duration for a complex, to be reconsidered afterwards. The case of B12 in a vegan diet is different: it is not a course but a permanent intake, as long as the diet continues.
Do B vitamins affect hair?
Only one claim allows this, that of biotin: "Biotin contributes to the maintenance of normal hair," from 7.5 µg per serving. It concerns the maintenance of normal function, not regrowth or density, and does not concern any scalp conditions. A little-known point: high-dose biotin intake can skew certain blood test results—report it before a blood test.
Should I take more after 50?
The relevant question at this age concerns B12, whose absorption from food becomes less efficient, and not the entire group. This is a point to discuss during a check-up, along with vitamin D — not a reason to proactively increase an already highly dosed B6 complex.
What brands are found in this section?
We prioritize labels that name the form of each vitamin rather than those that stack percentages. IO.Genix covers both needs of the section: a complete B complex, and a vegan 1,000 µg sustained-release B12. Now Foods offers a highly dosed methylated B12, a format consistent with the saturable absorption logic described above. Since a multivitamin often duplicates a B complex, choose one or the other. The rest of our micronutrition is in the vitamin C, vitamin E, zinc, magnesium, iron, and omega 3 sections; our sports nutrition guide explains each category, and the complete catalog is under sports nutrition.
Need advice at a store near Montpellier?
Our store in Vendargues, about ten minutes from Montpellier, is where we turn a box over to look at the only line that matters on a B complex: the vitamin B6 dosage. It's also where we most often advise against a purchase, because the person is already taking a multivitamin that covers the group. We ship everywhere in France and Europe. We will explain what a product contains; we will not tell you if you are lacking anything, as that question belongs to your doctor.
Sources: ANSES for nutritional references, Ciqual for food composition, EFSA for authorized claims and upper safety limits.
To go further: the role of vitamin B12 and signs of deficiency.
Un multivitamines à croquer, goût orange
Kid Vits réunit dix-sept vitamines et minéraux dans un comprimé à croquer aromatisé à la poudre de jus d'orange. La formule est conçue pour l'enfant à partir de quatre ans : deux comprimés par jour.
Le sucrant associe du sucre de canne et de l'extrait de feuille de stévia, pour 1 g de sucres par dose. La vitamine A est apportée à 100 % sous forme de bêta-carotène, le fer sous forme de glycinate (Albion™) et le zinc sous forme de bisglycinate.
Le flacon de 120 comprimés représente 60 doses, soit deux mois.
Composition par 2 comprimés à croquer
Autres ingrédients : sucre de canne, cellulose microcristalline, sorbitol, poudre de jus d'orange, acide stéarique d'origine végétale, acide L-malique, arômes naturels, maltodextrine (non-OGM), dioxyde de silicium, amidon de tapioca modifié, gomme d'acacia, alginate, concentré de balle de riz, amidon de pois, acide citrique, extrait de feuille de stévia (rébaudioside A), éthylcellulose, glycérine, hypromellose, tocophérols mélangés (tournesol), triglycérides à chaîne moyenne.
Sans blé, gluten, soja, lait, œuf, poisson, crustacés ni sésame ajoutés.
Questions fréquentes
À partir de quel âge ?
4 ans. Le produit n'est pas destiné aux enfants plus jeunes.
Combien de sucre par dose ?
1 g de sucres pour deux comprimés. Le reste du goût sucré vient de l'extrait de feuille de stévia et du sorbitol.
Quelle forme de vitamine A ?
100 % bêta-carotène, un précurseur végétal que l'organisme convertit selon ses besoins.
Pourquoi des minéraux sous forme de glycinate ?
Le fer et le zinc sont ici chélatés à un acide aminé (procédé Albion™), une forme choisie par NOW Foods pour sa tolérance digestive.
Un complexe B liquide, à prendre à la cuillère
Le B-12 Ultra liquide de NOW Foods est un complexe de vitamines B sous forme liquide, aromatisé naturellement à la cannelle, édulcoré au xylitol et à la stévia. Une cuillère à café (5 ml) apporte 5 000 µg de vitamine B12 sous trois formes, plus six autres vitamines B. Flacon de 118 ml, soit environ 24 cuillères.
Le format liquide intéresse ceux qui ont du mal à avaler les comprimés et ceux qui veulent pouvoir ajuster la dose à la demi-cuillère.
Deux points de dosage à connaître
2. La biotine : 300 µg par cuillère. La biotine peut fausser certains dosages sanguins, notamment ceux de la thyroïde (TSH, T3, T4) et de la troponine. Signalez à votre médecin et au laboratoire que vous prenez ce produit.
Les autres teneurs sont dans les clous : vitamine B6 à 10 mg pour un repère de 12,5 mg, niacine sous forme de niacinamide à 50 mg pour un repère de 450 mg, et aucune limite haute n'existe pour la B12, la B1, la B2, la biotine et l'acide pantothénique.
Une précision sur l'une des formes de B12
La vitamine B12 est apportée sous trois formes : cyanocobalamine, méthylcobalamine et dibencozide. Cette dernière ne figure pas parmi les sources de vitamine B12 listées à l'annexe européenne, qui retient la cyanocobalamine et la méthylcobalamine. Le total de 5 000 µg est celui déclaré par le fabricant et nous le reproduisons tel quel.
Ce que ces vitamines font, officiellement
- Fatigue et énergie : B2, B3, B6, B9, B12 et acide pantothénique contribuent à réduire la fatigue ; les sept contribuent à un métabolisme énergétique normal.
- Système nerveux et moral : B1, B2, B3, B6, biotine et B12 contribuent au fonctionnement normal du système nerveux ; B1, B3, B6, biotine, B9, B12 et acide pantothénique à des fonctions psychologiques normales.
- Sang : B6, B9 et B12 contribuent à la formation normale de globules rouges et au métabolisme normal de l'homocystéine.
- Immunité : B6, B9 et B12 contribuent au fonctionnement normal du système immunitaire.
- Peau, cheveux, muqueuses : la biotine contribue au maintien de cheveux et d'une peau normaux ; B2, B3 et biotine au maintien de muqueuses normales.
- Divers : la B1 contribue au fonctionnement normal du cœur ; la B2 au maintien d'une vision normale, de globules rouges normaux et au métabolisme normal du fer ; l'acide pantothénique à des performances intellectuelles normales.
Questions fréquentes
Pourquoi conseillez-vous une demi-cuillère ?
Uniquement à cause de l'acide folique : 800 µg par cuillère entière dépassent le repère français de 500 µg. À la demi-cuillère, on est à 400 µg — dans le repère — et il reste 2 500 µg de B12, ce qui est très largement suffisant. Le flacon dure aussi deux fois plus longtemps.
Quel goût ?
Cannelle, avec une douceur de xylitol et de stévia. Le fabricant demande de garder le liquide trente secondes en bouche, ce qui laisse le temps de l'apprécier — ou pas.
Faut-il vraiment le mettre au frigo ?
Oui, après ouverture : c'est l'instruction du fabricant, pour préserver la fraîcheur du produit. Le conservateur utilisé est le sorbate de potassium.
Liquide ou pastilles ?
Le liquide permet de fractionner la dose, ce qui est précisément son intérêt ici. Les pastilles sont plus simples, plus économiques et se transportent. À vous de voir ce que vous tiendrez dans le temps.
Disponible à Vendargues
Ce produit est aussi en rayon à la boutique Kiss Nutrition, 285 Rue des Portes Domitiennes, 34740 Vendargues.
Voir aussi notre rayon Vitamine B et la gamme complète NOW Foods.
La Now Foods Levure Alimentaire en Poudre est une levure séchée enrichie en six vitamines B. Une dose d'une cuillère à soupe rase (10 g) apporte 5 g de protéines, 2 g de fibres et des apports élevés en thiamine, riboflavine, niacine, vitamine B6, folates et vitamine B12. Végétalienne. Pot de 284 g, soit environ 28 doses.
C'est une levure enrichie, pas une levure naturellement riche
Disons-le d'emblée, parce que c'est souvent présenté de travers : les vitamines B de ce produit sont ajoutées. Le fabricant l'écrit — « enrichie en vitamines B supplémentaires » — et les vitamines figurent dans la liste d'ingrédients, après la levure séchée. Ce n'est ni mieux ni moins bien qu'une levure non enrichie, mais ce n'est pas la même chose, et la vitamine B12 en particulier ne provient pas de la levure : une levure n'en produit pas.
C'est précisément ce qui rend ce produit intéressant pour une alimentation végétalienne : il apporte de la B12, que les aliments végétaux ne contiennent pas.
Ce que la composition permet d'affirmer
- La thiamine (B1) contribue au métabolisme énergétique normal et au fonctionnement normal du système nerveux.
- La riboflavine (B2) contribue au métabolisme énergétique normal, au maintien de muqueuses normales et à la réduction de la fatigue.
- La niacine (B3) contribue au métabolisme énergétique normal et au maintien d'une peau normale.
- La vitamine B6 contribue au métabolisme normal des protéines et du glycogène, au métabolisme normal de l'homocystéine et à la réduction de la fatigue.
- Les folates contribuent à la synthèse normale des acides aminés et au fonctionnement normal du système immunitaire.
- La vitamine B12 contribue à la formation normale de globules rouges, au fonctionnement normal du système nerveux et à la réduction de la fatigue.
Composition
Ingrédients : levure séchée, niacine, chlorhydrate de pyridoxine (B6), riboflavine, chlorhydrate de thiamine, acide folique, cobalamine (B12).
Végétalienne, certifiée Casher et produite dans un site certifié SQF. Le fabricant indique que le produit n'est pas fabriqué avec des ingrédients à base de blé, gluten, soja, lait, œuf, poisson, crustacés ni fruits à coque. Il s'agit en revanche de levure : si vous y êtes sensible, ce produit n'est pas pour vous.
Questions fréquentes
Les vitamines B sont-elles naturellement présentes ?
Non, elles sont ajoutées : le fabricant indique que la levure est enrichie, et les vitamines figurent dans la liste d'ingrédients. La vitamine B12 en particulier ne peut pas venir de la levure, qui n'en produit pas.
Est-ce intéressant pour une alimentation végétalienne ?
C'est sa principale particularité : le produit apporte 15 µg de vitamine B12 par dose, et les aliments végétaux n'en contiennent pas.
Est-ce végétalien ?
Oui, et le fabricant le certifie.
Quel goût a-t-elle ?
C'est une levure alimentaire : son goût est caractéristique, souvent décrit comme fromagé. Elle se prête mieux à la cuisine qu'à l'eau pure.
La Now Foods Pantéthine 600 mg Double Strength apporte 600 mg de pantéthine par capsule molle. Flacon de 60 capsules molles. C'est la seule référence du catalogue sous cette forme.
La pantéthine, et pourquoi elle est à part
Deux conséquences très concrètes, et nous les disons parce qu'elles sont inhabituelles.
Composition
Autres ingrédients : enveloppe de la capsule molle (gélatine, glycérine, eau, caroube), huile de son de riz, cire d'abeille et lécithine de soja.
Deux points d'honnêteté sur cette liste. D'abord, le fabricant ne précise pas l'origine de la gélatine — ni bovine, ni porcine, ni de poisson. Ensuite, la formule contient du soja (lécithine), allergène à déclaration obligatoire — c'est pourquoi le soja ne figure pas dans la liste des allergènes que le fabricant déclare absents (levure, blé, gluten, lait, œuf, poisson, crustacés, fruits à coque).
Le flacon contient un sachet de fraîcheur, que le fabricant demande de ne pas consommer et de laisser dans le flacon.
Questions fréquentes
Combien de vitamine B5 cela représente-t-il ?
L'étiquette ne le dit pas : elle déclare 600 mg de pantéthine, sans équivalence en acide pantothénique et sans pourcentage des valeurs de référence. Nous ne ferons pas la conversion à la place du fabricant.
Contient-elle du soja ?
Oui, sous forme de lécithine de soja, allergène à déclaration obligatoire.
La forme la plus aboutie de la vitamine B5
La pantéthine est un dérivé de l'acide pantothénique — la vitamine B5 — et une étape avancée de la voie qui mène au coenzyme A, un cofacteur central du métabolisme des lipides et des glucides.
C'est une forme reconnue comme source de vitamine B5 dans les compléments alimentaires européens, et une référence nettement moins courante que le pantothénate de calcium.
NOW Foods la dose à 300 mg par capsule molle, en suspension dans de l'huile de son de riz. Le flacon de 60 capsules couvre deux mois.
Composition par capsule molle
Apport de référence non établi pour la pantéthine en tant que telle.
Autres ingrédients : capsule molle [gélatine bovine, glycérine, eau, caroube], huile de son de riz, lécithine de tournesol, cire d'abeille.
Capsule molle à base de gélatine bovine : le produit ne convient ni aux végétariens ni aux végétaliens. Sans levure, blé, gluten, soja, lait, œuf, poisson, crustacés ni fruits à coque ajoutés.
Questions fréquentes
Quelle différence avec le pantothénate de calcium ?
Le pantothénate de calcium est le sel de l'acide pantothénique, la forme la plus courante de vitamine B5. La pantéthine se situe plus loin sur la voie métabolique, plus près du coenzyme A.
Qu'est-ce que le coenzyme A ?
Un cofacteur présent dans toutes les cellules, impliqué dans le métabolisme des acides gras et dans le cycle de Krebs. La pantéthine en est un précurseur.
Pourquoi une capsule molle à l'huile ?
La pantéthine est hygroscopique : elle capte l'humidité. La mise en suspension dans de l'huile de son de riz, à l'intérieur d'une capsule molle, la stabilise.
Le produit convient-il aux végétariens ?
Non. L'enveloppe est en gélatine bovine et la formule contient de la cire d'abeille.
Une pastille à laisser fondre, pas de verre d'eau
La Vitamine B12 1000 µg de NOW Foods se présente en pastilles à croquer ou à laisser fondre en bouche, aromatisées naturellement et sucrées au xylitol et à la stévia — sans sucre ajouté. Chaque pastille apporte 1 000 µg de vitamine B12 (cyanocobalamine) et 100 µg d'acide folique.
Sur une prise quotidienne au long cours — ce qui est le cas pour la plupart des gens qui se supplémentent en B12 — le format compte autant que la formule : une pastille au goût agréable, sans eau, s'oublie beaucoup moins qu'un comprimé à avaler. Flacons de 100 ou 250 pastilles, soit trois ou huit mois.
Ce que ces deux vitamines font, officiellement
La vitamine B12 contribue à un métabolisme énergétique normal, au fonctionnement normal du système nerveux, au métabolisme normal de l'homocystéine, à des fonctions psychologiques normales, à la formation normale de globules rouges, au fonctionnement normal du système immunitaire, à réduire la fatigue, et joue un rôle dans le processus de division cellulaire.
À qui cela s'adresse
La vitamine B12 est présente presque exclusivement dans les produits d'origine animale. Trois situations la rendent pertinente, et le fabricant les nomme lui-même :
- les régimes végétariens et surtout végétaliens, où la supplémentation fait partie des bases ;
- les personnes âgées, chez qui l'absorption digestive diminue ;
- les statuts bas constatés par une prise de sang, sous suivi médical.
Un conseil pratique : si vous n'avez jamais fait doser votre B12, faites-le avant de commencer. Cela donne un point de départ clair et permet d'évaluer l'effet de la cure ensuite.
Questions fréquentes
Pourquoi une pastille à sucer plutôt qu'un comprimé ?
Pour le confort, surtout : pas d'eau à prévoir, un goût agréable, une prise qui se tient dans le temps.
Cyanocobalamine ou méthylcobalamine ?
La cyanocobalamine est la forme la plus étudiée et la plus stable ; l'organisme la convertit en formes actives. La méthylcobalamine est une forme co-enzyme, directement utilisable. Si vous préférez la forme méthylée, voyez notre Methyl B-12.
Est-ce que 1 000 µg c'est trop ?
Aucune dose journalière maximale n'est fixée pour la vitamine B12 : c'est une vitamine hydrosoluble sans limite haute établie. Le dosage élevé compense la faible absorption digestive.
Est-ce végane ?
Oui. Aucun ingrédient d'origine animale : la B12 est produite par fermentation bactérienne, l'acide stéarique est d'origine végétale. C'est cohérent, puisque les végétaliens sont le premier public de ce produit.
Quel format choisir ?
Le 100 pastilles pour commencer ou tester le goût ; le 250 si la B12 est installée durablement dans votre routine — le prix à la pastille y est plus bas.
Disponible à Vendargues
Ce produit est aussi en rayon à la boutique Kiss Nutrition, 285 Rue des Portes Domitiennes, 34740 Vendargues. Notre première question sera simple : avez-vous fait doser votre B12 ? C'est ce qui permet de bien calibrer la cure.
Voir aussi notre rayon Vitamine B et la gamme complète NOW Foods.
De la vitamine B3 sans l'effet flush
Le Niacinamide de NOW Foods apporte 1 000 mg de vitamine B3 par comprimé sous forme de niacinamide (nicotinamide) — la forme qui ne provoque pas le « flush », cette bouffée de rougeur et de chaleur du visage et du buste que donne l'acide nicotinique. 90 comprimés, soit trois mois.
C'est une distinction importante et souvent mal comprise. « Niacine », « vitamine B3 » et « PP » désignent la même vitamine, mais sous deux formes aux comportements très différents.
Niacinamide ou acide nicotinique : la différence compte
Autrement dit, la forme retenue ici est celle qui autorise des dosages sans commune mesure avec l'autre. Cela ne veut pas dire que tout est permis pour autant.
Le point de dosage, dit franchement
Ce comprimé contient 1 000 mg de niacinamide, soit un peu plus du double de la dose journalière maximale de 450 mg recommandée en France. C'est à savoir avant d'acheter.
Ce que la niacine fait, officiellement
- à un métabolisme énergétique normal ;
- au fonctionnement normal du système nerveux ;
- à des fonctions psychologiques normales ;
- au maintien de muqueuses normales ;
- au maintien d'une peau normale ;
- à réduire la fatigue.
Questions fréquentes
Est-ce que ça va me faire rougir ?
Non, et c'est tout l'intérêt de cette forme. Le flush est propre à l'acide nicotinique ; le niacinamide n'en provoque pas.
Niacinamide ou nicotinamide riboside ?
Ce sont deux molécules différentes de la famille de la B3, avec des positionnements commerciaux distincts. Ce produit contient du niacinamide classique, pas du nicotinamide riboside.
Peut-on couper le comprimé ?
Il est pelliculé, mais sécable : si vous voulez descendre à 500 mg par jour, c'est tout à fait faisable, et cela vous rapproche du repère français.
Disponible à Vendargues
Voir aussi notre rayon Vitamine B et la gamme complète NOW Foods.
Qu'est-ce que la Biotine 1 000 µg de Now Foods ?
C'est de la biotine en gélules végétales, dosée à 1 000 µg par gélule. La biotine, aussi appelée vitamine B8 ou vitamine H, est une vitamine hydrosoluble du groupe B.
C'est le dosage d'entrée de la gamme : la marque propose aussi des versions à 5 mg et à 10 mg. Le reste de la gamme est dans notre rayon Now Foods.
Ce qu'il y a dans la Biotine 1 000 µg
Une gélule, 1 000 µg de biotine, et rien d'autre d'actif.
La biotine contribue au métabolisme énergétique normal, au métabolisme normal des macronutriments, au fonctionnement normal du système nerveux, aux fonctions psychologiques normales, et au maintien de cheveux normaux, d'une peau normale et de muqueuses normales.
La liste des autres ingrédients tient en quatre lignes : farine de riz, hypromellose (l'enveloppe de la gélule), palmitate d'ascorbyle et dioxyde de silicium. Le produit est végétalien, et sans blé, gluten, soja, lait, œuf, poisson, crustacés, fruits à coque ni sésame ajoutés.
À qui s'adresse la Biotine 1 000 µg ?
À ceux qui veulent commencer par le dosage le plus bas de la gamme, et à ceux qui prennent déjà plusieurs compléments et préfèrent un apport mesuré plutôt qu'un dosage élevé.
C'est aussi le format de ceux qui cherchent une vitamine B8 seule, sans la noyer dans un complexe cheveux et ongles où elle arrive mélangée à dix autres actifs. La gélule est petite, sans goût, et s'avale avec un verre d'eau.
Questions fréquentes
Biotine, vitamine B8 ou vitamine H ?
Ce sont trois noms de la même vitamine hydrosoluble du groupe B. « Biotine » est le nom courant, « vitamine B8 » le nom français, « vitamine H » un nom plus ancien.
Combien de biotine par gélule ?
1 000 µg, soit 1 mg, par gélule végétale.
Est-ce végétalien ?
Oui. L'enveloppe est en hypromellose d'origine végétale et la formule ne contient aucun ingrédient animal.
Y a-t-il des allergènes ?
Le produit est sans blé, gluten, soja, lait, œuf, poisson, crustacés, fruits à coque ni sésame ajoutés.
À quoi sert la biotine ?
Elle contribue au métabolisme énergétique normal, au métabolisme normal des macronutriments, et au maintien de cheveux normaux, d'une peau normale et de muqueuses normales.
Pourquoi la prendre seule ?
Pour maîtriser l'apport. Dans un complexe cheveux et ongles, la biotine arrive mélangée à d'autres actifs que l'on ne souhaite pas forcément.
Où acheter la Biotine 1 000 µg de Now Foods ?
Le flacon se commande depuis cette page, et nous expédions partout en France et en Europe. Notre magasin se trouve à Vendargues, à une dizaine de minutes de Montpellier.
Le reste de la marque se parcourt dans la collection Now Foods.
Le complexe B à dosage élevé
La Vitamine B-100 de NOW Foods réunit les huit vitamines du groupe B à 100 mg (ou 100 µg pour celles qui se comptent en microgrammes), plus de la choline, de l'inositol et du PABA. Une gélule végétale par jour, au repas. Flacons de 100 ou 250 gélules.
C'est le format le plus dosé du complexe B de NOW. Sa petite sœur, la B-50, divise tout par deux — et pour beaucoup de gens c'est le choix plus sage. Voici pourquoi.
À lire avant de commander : la vitamine B6
Notre position, sans détour : ce produit n'est pas un complexe B d'entretien quotidien. Si vous le prenez, faites-le en cure courte et de préférence avec l'accord de votre médecin. Pour un usage régulier, prenez la B-50, ou mieux, demandez-nous conseil : il existe des complexes B aux dosages alignés sur les repères français.
Ce qui est en revanche très bien calibré
- La niacine (B3) : apportée sous forme de niacinamide et non d'acide nicotinique. Pas d'effet « flush » (rougeur et chaleur du visage), et un plafond français de 450 mg — les 100 mg de la gélule sont confortablement en dessous. Pour mémoire, le plafond de l'acide nicotinique, lui, est de 8 mg.
- Les folates : 400 µg d'acide folique, sous le repère français de 500 µg par jour.
- La vitamine B12 : 100 µg. Aucune limite haute n'est établie pour la B12, hydrosoluble et éliminée par les urines.
Attention aux analyses de sang
Ce produit contient de la biotine, et le fabricant le signale lui-même sur l'étiquette : la biotine peut fausser certains dosages sanguins, en particulier ceux de la thyroïde (TSH, T3, T4) et de la troponine, dans un sens comme dans l'autre. Signalez toujours à votre médecin et au laboratoire que vous prenez de la biotine ; c'est à votre médecin de dire s'il faut interrompre la prise avant un prélèvement.
Ce que ces vitamines font, officiellement
- Fatigue et énergie : B2, B3, B6, B9, B12 et acide pantothénique contribuent à réduire la fatigue ; les huit contribuent à un métabolisme énergétique normal.
- Système nerveux et moral : B1, B2, B3, B6, biotine et B12 contribuent au fonctionnement normal du système nerveux ; B1, B3, B6, biotine, B9, B12 et acide pantothénique à des fonctions psychologiques normales.
- Sang : B6, B9 et B12 contribuent à la formation normale de globules rouges et au métabolisme normal de l'homocystéine.
- Immunité : B6, B9 et B12 contribuent au fonctionnement normal du système immunitaire.
- Peau, cheveux, muqueuses : la biotine contribue au maintien de cheveux et d'une peau normaux ; B2, B3 et biotine au maintien de muqueuses normales.
- Divers : la B1 contribue au fonctionnement normal du cœur ; la B2 au maintien d'une vision normale et au métabolisme normal du fer ; la B6 à la régulation de l'activité hormonale.
Questions fréquentes
B-100 ou B-50 ?
La B-50 dans la grande majorité des cas. Les vitamines B sont hydrosolubles : au-delà d'un certain seuil, l'excédent est éliminé, et doubler la dose ne double pas le bénéfice. Le seul argument en faveur de la B-100 serait un besoin particulier identifié par un professionnel de santé.
Est-ce que les fortes doses de B12 sont dangereuses ?
Aucune limite haute n'est établie pour la vitamine B12. C'est la B6 qui pose la question sur ce produit, pas la B12.
Pourquoi 680 µg de folates sur l'étiquette américaine ?
Parce que les États-Unis expriment les folates en « équivalents folates alimentaires » (DFE). En Europe, c'est la quantité réelle d'acide folique qui compte : 400 µg. C'est la valeur que nous affichons.
Disponible à Vendargues
Ce produit est aussi en rayon à la boutique Kiss Nutrition, 285 Rue des Portes Domitiennes, 34740 Vendargues. Sur les complexes B à dosage élevé, venez nous en parler : deux minutes de discussion valent mieux qu'un achat à l'aveugle.
Voir aussi notre rayon Vitamine B et la gamme complète NOW Foods.
Le dosage le plus élevé de la gamme
NOW Foods décline la biotine en trois dosages : 1 mg, 5 mg et 10 mg. Cette référence est la plus concentrée — 10 mg, soit 10 000 µg par gélule végétale.
La biotine (vitamine B8) est une vitamine hydrosoluble du groupe B. Elle contribue au métabolisme énergétique normal, au métabolisme normal des macronutriments, au fonctionnement normal du système nerveux, aux fonctions psychologiques normales, et au maintien de cheveux normaux, d'une peau normale et de muqueuses normales.
La formule est volontairement minimale : de la biotine, de la farine de riz, une gélule végétale et deux excipients techniques.
Composition par gélule végétale
Autres ingrédients : farine de riz, hypromellose (gélule d'origine végétale), dioxyde de silicium, acide stéarique (source végétale).
Végétalien. Sans blé, gluten, soja, maïs, lait, œuf, poisson, crustacés, fruits à coque ni sésame ajoutés.
Questions fréquentes
Quelle est la différence avec les versions 1 mg et 5 mg ?
Uniquement le dosage de biotine : 1 mg, 5 mg ou 10 mg par gélule. La formulation et la forme galénique sont les mêmes.
La biotine peut-elle perturber une analyse de sang ?
Oui, et c'est particulièrement à surveiller à ce dosage. La biotine à forte dose peut fausser certains dosages biologiques, notamment thyroïdiens et cardiaques. Prévenez le laboratoire et votre médecin avant tout bilan sanguin.
Est-ce végétalien ?
Oui. La gélule est d'origine végétale et la formule ne contient aucun ingrédient animal.
Retrait au magasin sous 2 h
À Vendargues, près de Montpellier. Vous êtes prévenu dès que la commande est prête.
Commandé avant 14 h, expédié le jour même
Du lundi au samedi. Le délai d'acheminement appartient ensuite au transporteur.
Livraison offerte dès 69 €
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What do the eight B vitamins do?
"Vitamin B" does not exist in the singular. The B group brings together eight distinct vitamins, unrelated chemically, united by a common history: it was believed that a single water-soluble factor had been isolated before it was understood that it contained several. They share two practical properties: water-soluble, thus poorly stored and eliminated through urine, they almost all act as coenzymes in energy production.
Each carries its own European-authorized health claims, with wording regulated to the word, usable as soon as the product is a "source of" the vitamin concerned, meaning 15% of its nutritional reference value per serving.
- B1, thiamine (NRV 1.1 mg) — coenzyme in carbohydrate metabolism. "Thiamine contributes to normal energy-yielding metabolism."
- B2, riboflavin (NRV 1.4 mg) — FAD precursor, electron carrier. "Riboflavin contributes to normal iron metabolism."
- B3, niacin (NRV 16 mg) — NAD precursor, present in hundreds of reactions. "Niacin contributes to the reduction of tiredness and fatigue."
- B5, pantothenic acid (NRV 6 mg) — component of coenzyme A. "Pantothenic acid contributes to normal mental performance."
- B6, pyridoxine (NRV 1.4 mg) — coenzyme in amino acid metabolism. "Vitamin B6 contributes to normal protein and glycogen metabolism."
- B8, biotin (NRV 50 µg) — coenzyme of carboxylases. "Biotin contributes to the maintenance of normal hair."
- B9, folate (NRV 200 µg) — one-carbon group transfer, DNA synthesis. "Folate has a role in the process of cell division."
- B12, cobalamin (NRV 2.5 µg) — coenzyme for only two, but critical, reactions. "Vitamin B12 contributes to normal red blood cell formation."
Six of them — B2, B3, B5, B6, B9, and B12 — also carry the claim "contributes to the reduction of tiredness and fatigue." It means what it says: a contribution, for those who are deficient. It does not make a B complex a stimulant.
Why are they sold as a complex rather than individually?
Three reasons, only two of which are good.
Biochemistry first: these vitamins work in series on the same pathways. Pyruvate from carbohydrates needs B1, B2, B3, and B5 to be oxidized; homocysteine metabolism jointly mobilizes B6, B9, and B12. Providing one without the others only makes sense if a precise point is targeted.
Food sources then: they largely overlap. Offal, meats, eggs, dairy products, legumes, whole grains, green vegetables, and yeasts cover the group fairly homogeneously. A diet poor in one B vitamin is often poor in several — the major exception being B12.
The third reason is commercial: a complex sells better than a single capsule. A "B complex" at 500 or 1000% of NRVs offers nothing more than a reasonable dosage if your intake is adequate, as the excess water-soluble portion is excreted in the urine. The useful benchmark is not the percentage but the adequacy with what you are already taking: many multivitamins cover the entire B group, and combining the two is wasteful.
Why is B12 not optional in a vegan diet?
This is the only case in this entire catalog where we state that supplementation is necessary and not merely useful.
B12 is synthesized only by bacteria. It is found in animal products because these bacteria live in the digestive tract of ruminants, or because the animal has consumed it. No plant contains it in an active form: neither legumes, grains, vegetables, nor any fruit. A strict vegan diet therefore ultimately leads to zero intake.
Two misleading ideas circulate. Spirulina and several algae show "B12" contents that mainly correspond to inactive analogues: these molecules resemble B12 without having its activity and can occupy the same transporters. Spirulina is interesting for other reasons, but it is not a source of B12. Plant proteins, unenriched nutritional yeast, and fermented foods are also not reliable sources.
Key implementation point: B12 absorption is saturable. Active transport, which depends on intrinsic factor secreted by the stomach, only handles a very small amount per intake; the rest only passes through passive diffusion, at about 1% of the dose. Hence, supplements are dosed well above the NRV of 2.5 µg, and weekly high-dose intake is common. The precise regimen—dose, frequency, biological control—should be decided with a doctor.
Methylcobalamin, methylfolate, P5P: Are active forms worth their price?
The commercial argument is always the same: the form sold would be "already active," hence superior to what the body must convert. What can be said honestly:
Methylcobalamin versus cyanocobalamin. Cyanocobalamin is the most stable and well-documented; the body detaches the cyanide group from it, in negligible quantity, and converts it into active forms—including methylcobalamin. The latter is perfectly valid but less stable to light, and no European claim distinguishes it: both carry the same wording.
Methylfolate versus folic acid. Same logic: 5-methyltetrahydrofolate is the circulating form; folic acid must be reduced then methylated, a conversion that MTHFR gene variants slow down in a portion of the population. Methylfolate is a good choice, but folic acid carries most of the available data.
P5P versus pyridoxine. Pyridoxal 5-phosphate (P5P) is the coenzymatic form of B6. A rarely mentioned detail: ingested P5P is in any case dephosphorylated in the intestine before being absorbed, then rephosphorylated in the liver. The theoretical advantage is therefore thinner than advertised, except in specific situations requiring a doctor's advice.
Active forms are therefore not an empty argument, but neither are they the revolution that the price suggests: they do not render classic forms ineffective.
What dose, and what are the safety limits?
Water solubility reassuringly misleads. Three B vitamins have a European upper safety limit, and these are precisely the ones often overdosed in high-percentage complexes.
Vitamin B6 is the most monitored: the European safety limit has been revised downwards and is set at 12 mg per day for adults, from all sources combined. High and prolonged intake of B6 is associated with peripheral nerve damage. However, many B complexes display 25 mg or 50 mg of B6 without any justification — and ZMA formulas also contain it.
Niacin comes in two forms: nicotinic acid, whose limit is very low due to the flushing it causes, and nicotinamide, which is much better tolerated and by far the most commonly used. The mention of the form on the label is therefore important.
Folic acid has a limit set at 1,000 µg per day for adults. High intake can mask a B12 deficiency biologically, which is a serious reason not to stack sources.
Medical advice is essential before any supplementation during pregnancy or breastfeeding — recommendations on folate around conception are precise and fall under the purview of a healthcare professional — for children and adolescents, in cases of kidney failure, during long-term treatment, or in cases of chronic illness.
Frequently Asked Questions
What are B vitamins?
Eight distinct vitamins, chemically unrelated, grouped under the same letter by historical accident: it was long believed that a single water-soluble factor had been isolated before it was discovered that it contained several, hence the gapped numbering we know — B1, B2, B3, B5, B6, B8, B9, B12. They have only two things in common. They are water-soluble, therefore poorly stored and eliminated through urine, requiring regular intake. And almost all act as coenzymes: they provide no energy themselves; they enable enzymes to extract energy from food. This is why a B complex is not a stimulant.
What is the role of B vitamins?
Three main roles, distributed differently depending on the vitamin. First, energy metabolism: B1, B2, B3, and B5 enable the oxidation of carbohydrates, fats, and proteins to produce ATP. Second, DNA synthesis and repair, carried out by folates (B9) and B12, which explains their importance in cell division and red blood cell formation. Finally, the functioning of the nervous system, where B6 is involved in the production of several neurotransmitters and B12 in the maintenance of the myelin sheath. Additionally, B6 plays a role in protein metabolism, particularly stressed in athletes with high protein intake.
How to take a B vitamin complex?
Once a day, with a meal and preferably in the morning or at noon. Taking it with a meal reduces nausea that some formulas cause on an empty stomach; taking it in the morning avoids sleep disturbances reported by some people with highly dosed complexes. Three practical points are more important than the timing. Add up your sources: if you already take a multivitamin or ZMA, a B complex is redundant and increases B6 intake. Check the B6 dose, the only truly sensitive line of a complex. And don't rely on percentages: 1000% of NRVs doesn't make it ten times better, the excess water-soluble portion is excreted in the urine.
Why does urine become bright yellow?
It's riboflavin, vitamin B2: a fluorescent yellow pigment, hence its old name lactoflavin. The unused excess is filtered by the kidneys and colors the urine within a few hours. The phenomenon is harmless and does not indicate a problem or good assimilation: it signals that the dose exceeded what your body could use. Persistent discoloration without supplement intake, however, should be reported to a doctor.
What are the symptoms of a B vitamin deficiency?
First, it must be said why the question is poorly phrased: the eight B vitamins have different roles, and a lack of B1 is not like a lack of B12. Furthermore, proven deficiencies have become rare in France, except in specific situations — vegan diet without supplementation, chronic alcoholism, malabsorption, digestive surgery, malnutrition. The manifestations described in medical literature are severe and specific: anemia and neurological disorders for B12 and folate, nerve damage for B1, skin and mucous membrane lesions for B2 and B3. Vague symptoms often invoked online — fatigue, low mood, dull hair — do not allow for any conclusions: they are shared with dozens of other situations. Doubt is raised by a blood test prescribed by a doctor, not by a purchase.
In which foods are B vitamins found?
Offal and liver cover almost the entire group. Then come meats, fish, eggs and dairy products for B2, B3, B6 and B12; legumes, whole grains and seeds for B1, B6 and B9; leafy green vegetables for folate, whose name comes from the Latin folium, the leaf; brewer's yeast for the entire group except B12.
Which fruit is richest in vitamin B12?
None, and that's the complete answer: B12 is bacterial in origin and is not present in any fruit or vegetable. The richest foods are liver, offal, shellfish and fish, then meat, eggs, and dairy products. For folate (B9), however, citrus fruits, leafy green vegetables, and legumes are good sources.
What are the reasons for a vitamin B12 deficiency?
Two very different mechanisms, which do not call for the same response. The first is insufficient intake: a vegan diet without supplementation, or a diet very low in animal products — this is the only situation where an over-the-counter supplement directly addresses the problem. The second is defective absorption, and it is medical: B12 needs gastric acid to be released from food proteins, then intrinsic factor secreted by the stomach to be absorbed in the ileum. Anything that disrupts this chain causes it to drop: age, which reduces gastric secretion, certain long-term treatments, stomach or intestinal surgeries, inflammatory bowel diseases, and pernicious anemia. In this second case, increasing dietary intake does not solve anything: a blood test and a doctor are needed.
How to detect a vitamin B12 deficiency?
By a blood test prescribed and interpreted by a doctor, and by nothing else. Serum B12 levels are the first test, but they are imperfect: a "borderline" level has no clear meaning, and the doctor may request additional markers — homocysteine, methylmalonic acid — as well as a blood count. Two pitfalls are worth knowing. A high intake of folic acid can correct anemia while allowing neurological damage to progress, which masks the problem. And starting to supplement before testing skews the result: if you suspect a deficiency, get tested first. No symptom, no self-test, and no web page can replace this approach.
How to raise B12 levels?
This question is for a doctor, not a dietary supplement: depending on the cause, high-dose oral and injectable routes do not have the same place, and biological monitoring is part of the treatment. A general public supplement ensures intake for a healthy person; it does not correct a diagnosed anomaly.
How long does a course of B vitamins last?
One to three months is the common duration for a complex, to be reconsidered afterwards. The case of B12 in a vegan diet is different: it is not a course but a permanent intake, as long as the diet continues.
Do B vitamins affect hair?
Only one claim allows this, that of biotin: "Biotin contributes to the maintenance of normal hair," from 7.5 µg per serving. It concerns the maintenance of normal function, not regrowth or density, and does not concern any scalp conditions. A little-known point: high-dose biotin intake can skew certain blood test results—report it before a blood test.
Should I take more after 50?
The relevant question at this age concerns B12, whose absorption from food becomes less efficient, and not the entire group. This is a point to discuss during a check-up, along with vitamin D — not a reason to proactively increase an already highly dosed B6 complex.
What brands are found in this section?
We prioritize labels that name the form of each vitamin rather than those that stack percentages. IO.Genix covers both needs of the section: a complete B complex, and a vegan 1,000 µg sustained-release B12. Now Foods offers a highly dosed methylated B12, a format consistent with the saturable absorption logic described above. Since a multivitamin often duplicates a B complex, choose one or the other. The rest of our micronutrition is in the vitamin C, vitamin E, zinc, magnesium, iron, and omega 3 sections; our sports nutrition guide explains each category, and the complete catalog is under sports nutrition.
Need advice at a store near Montpellier?
Our store in Vendargues, about ten minutes from Montpellier, is where we turn a box over to look at the only line that matters on a B complex: the vitamin B6 dosage. It's also where we most often advise against a purchase, because the person is already taking a multivitamin that covers the group. We ship everywhere in France and Europe. We will explain what a product contains; we will not tell you if you are lacking anything, as that question belongs to your doctor.
Sources: ANSES for nutritional references, Ciqual for food composition, EFSA for authorized claims and upper safety limits.
To go further: the role of vitamin B12 and signs of deficiency.
Sources
- ANSES — Les compléments alimentaires
- Règlement UE n° 432/2012 — allégations de santé autorisées
- Règlement CE n° 1924/2006 — allégations nutritionnelles et de santé
À intégrer dans une alimentation variée et équilibrée et un mode de vie sain.
Questions fréquentes — Vitamin B Complex
Les vitamines B, c'est quoi ?
Huit vitamines distinctes, sans parenté chimique entre elles, regroupées sous une même lettre par accident historique : on a longtemps cru avoir isolé un seul facteur hydrosoluble avant de découvrir qu'il en contenait plusieurs, d'où la numérotation trouée que l'on connaît — B1, B2, B3, B5, B6, B8, B9, B12. Elles ont deux points communs seulement. Elles sont hydrosolubles, donc peu stockées et éliminées par les urines, ce qui impose un apport régulier. Et elles agissent presque toutes comme coenzymes : elles ne fournissent aucune énergie par elles-mêmes, elles permettent aux enzymes d'extraire celle des aliments. C'est pourquoi un complexe B n'est pas un stimulant.
Quel est le rôle des vitamines B ?
Trois grands rôles, répartis différemment selon la vitamine. Le métabolisme énergétique d'abord : B1, B2, B3 et B5 permettent d'oxyder glucides, lipides et protéines pour en tirer de l'ATP. La synthèse et la réparation de l'ADN ensuite, portées par les folates (B9) et la B12, ce qui explique leur importance dans la division cellulaire et la formation des globules rouges. Le fonctionnement du système nerveux enfin, où la B6 intervient dans la fabrication de plusieurs neurotransmetteurs et la B12 dans le maintien de la gaine de myéline. S'y ajoute le rôle de la B6 dans le métabolisme des protéines, particulièrement sollicité chez les sportifs à apport protéique élevé.
Comment prendre un complexe de vitamines B ?
Une prise par jour, au cours d'un repas et de préférence le matin ou à midi. Le repas limite les nausées que provoquent certaines formules à jeun ; le matin évite la gêne à l'endormissement que rapportent certaines personnes avec les complexes fortement dosés. Trois points pratiques valent plus que l'horaire. Additionnez vos sources : une multivitamine ou un ZMA couvre déjà une partie du groupe, donc choisissez l'un ou l'autre et suivez le total de B6. Vérifiez la dose de B6, la ligne sensible d'un complexe. Et lisez les milligrammes plutôt que les pourcentages : l'excédent hydrosoluble part dans les urines, un dosage mesuré suffit.
Pourquoi les urines deviennent-elles jaune vif ?
C'est la riboflavine, la vitamine B2 : un pigment jaune fluorescent, d'où son ancien nom de lactoflavine. L'excédent non utilisé est filtré par le rein et colore les urines en quelques heures. Le phénomène est sans gravité et n'annonce ni un problème ni une bonne assimilation : il signale que la dose dépassait ce que votre organisme pouvait employer. Une coloration qui persiste sans prise de complément, elle, se signale à un médecin.
Quels sont les symptômes d'un manque de vitamine B ?
La réponse se décline par vitamine : les huit ont des rôles différents, et un manque de B1 ne ressemble pas à un manque de B12. Les carences avérées sont par ailleurs devenues rares en France, hors situations particulières — régime végétalien sans supplémentation, alcoolisme chronique, malabsorption, chirurgie digestive, dénutrition. Les manifestations décrites dans la littérature médicale sont sévères et spécifiques : anémie et troubles neurologiques pour la B12 et les folates, atteintes nerveuses pour la B1, lésions cutanées et des muqueuses pour la B2 et la B3. Les symptômes vagues souvent invoqués en ligne — fatigue, moral bas, cheveux ternes — sont partagés avec des dizaines d'autres situations : une prise de sang prescrite par un médecin est ce qui permet de conclure.
Dans quels aliments trouve-t-on les vitamines B ?
Les abats et le foie couvrent presque tout le groupe. Viennent les viandes, poissons, œufs et produits laitiers pour B2, B3, B6 et B12 ; les légumineuses, céréales complètes et graines pour B1, B6 et B9 ; les légumes verts à feuilles pour les folates, dont le nom vient du latin folium, la feuille ; la levure de bière pour tout le groupe hors B12.
Quel fruit est le plus riche en vitamine B12 ?
Aucun, et c'est la réponse complète : la B12 est d'origine bactérienne et n'est présente dans aucun fruit ni aucun légume. Les aliments les plus riches sont le foie, les abats, les coquillages et les poissons, puis les viandes, les œufs et les produits laitiers. Pour les folates (B9), les agrumes, les légumes verts à feuilles et les légumineuses sont en revanche de bonnes sources.
Quelles sont les raisons d'un manque de vitamine B12 ?
Deux mécanismes très différents, qui n'appellent pas la même réponse. Le premier est un apport insuffisant : régime végétalien sans supplémentation, ou alimentation très pauvre en produits animaux — c'est la seule situation où un complément grand public répond directement au problème. Le second est une absorption défaillante, et il est médical : la B12 a besoin de l'acidité gastrique pour être libérée des protéines alimentaires, puis du facteur intrinsèque sécrété par l'estomac pour être absorbée dans l'iléon. Tout ce qui perturbe cette chaîne la fait chuter : l'âge, qui réduit la sécrétion gastrique, certains traitements au long cours, les chirurgies de l'estomac ou de l'intestin, les maladies inflammatoires digestives et la maladie de Biermer. Dans ce second cas, augmenter les apports alimentaires ne résout rien : c'est une prise de sang et un médecin qu'il faut.
Comment détecter une carence en vitamine B12 ?
Par une prise de sang prescrite et interprétée par un médecin. Le dosage de la B12 sérique est le premier examen ; un taux dit « limite » n'a pas de signification claire, et le médecin peut demander des marqueurs complémentaires — homocystéine, acide méthylmalonique — ainsi qu'une numération sanguine. Deux points pratiques méritent d'être connus. Un apport élevé en acide folique peut corriger l'anémie tout en laissant progresser l'atteinte neurologique. Et commencer une supplémentation avant le dosage fausse le résultat : le bilan se fait d'abord.
Comment faire remonter un taux de B12 ?
Cette question se règle avec un médecin : selon la cause, la voie orale à forte dose et la voie injectable n'ont pas la même place, et le suivi biologique fait partie du traitement. Un complément alimentaire sécurise un apport chez une personne en bonne santé, ce qui est son rôle.
Combien de temps dure une cure de vitamines B ?
Un à trois mois est la durée courante pour un complexe, à reconsidérer ensuite. Le cas de la B12 en régime végétalien est différent : il ne s'agit pas d'une cure mais d'un apport permanent, aussi longtemps que dure le régime.
Les vitamines B agissent-elles sur les cheveux ?
Une seule allégation le permet, celle de la biotine : « La biotine contribue au maintien de cheveux normaux », à partir de 7,5 µg par portion. Elle porte sur le maintien d'une fonction normale, pas sur la repousse ni la densité, et ne concerne aucune affection du cuir chevelu. Point peu connu : une prise de biotine à forte dose peut fausser certains dosages sanguins — signalez-la avant une prise de sang.
Faut-il en prendre davantage après 50 ans ?
La question pertinente à cet âge porte sur la B12, dont l'absorption à partir des aliments devient moins efficace, et non sur le groupe entier. C'est un point à évoquer lors d'un bilan, en même temps que la vitamine D : la B12 se complète alors à part, plutôt qu'en augmentant un complexe entier.
