Vitamin B6 is everywhere: in meat, fish, potatoes and nuts, and in many supplements, often alongside magnesium. Essential to over a hundred bodily reactions, it can nevertheless damage nerves at high doses over time. Five things to know for safe use: forms, requirements, people at risk of deficiency, recognised roles and safety limits.
Key takeaways
- Vitamin B6 includes several forms; pyridoxal phosphate (PLP) is the active form, a coenzyme for over a hundred reactions.
- EFSA sets requirements at 1.7mg daily for men and 1.6mg for women, easily met through diet.
- Ten claims are authorised, including “contributes to the reduction of tiredness and fatigue” and “contributes to normal functioning of the nervous system”.
- In 2023, EFSA lowered its adult safety limit from 25 to 12mg daily because of neuropathy risk.
1. Vitamin B6 is not a single molecule
Vitamin B6 covers six related compounds: pyridoxine, pyridoxal, pyridoxamine and their phosphorylated forms. The active form is pyridoxal phosphate (PLP), a coenzyme in over a hundred enzymatic reactions, notably amino acid, carbohydrate and fat metabolism.
PLP enables production of key nervous system and body molecules: serotonin, dopamine, noradrenaline, histamine, GABA and taurine. This link appears in our articles on taurine and melatonin, made from serotonin.
Supplements mainly contain pyridoxine hydrochloride, around 95% absorbed according to EFSA, sometimes pyridoxal phosphate, often called P5P, already active. Absorption from a varied diet is around 75%, because pyridoxine glucoside, present in some plants, is only half as well absorbed.
2. Vitamin B6 requirements are easily met at the table
EFSA sets the dietary reference at 1.7mg daily for men and 1.6mg for women, 1.8mg during pregnancy and 1.7mg during breastfeeding. In children, it ranges from 0.6 to 1.7mg by age. These values target blood PLP of at least 30 nmol/l, considered adequate.
| Food | Vitamin B6 (mg per 100 g) | Illustrative serving | Amount per serving |
|---|---|---|---|
| Cooked heifer liver | 1.4 | 100 g | 1.4mg |
| Roasted pistachios | 1.3 | 30 g | 0.39mg |
| Sunflower seeds | 1.24 | 30 g | 0.37mg |
| Baked mackerel | 0.62 | 150 g | 0.93mg |
| Baked tuna | 0.47 | 150 g | 0.71mg |
| Cooked salmon | 0.46 | 150 g | 0.69mg |
| Cooked pork | 0.36 | 125 g | 0.45mg |
| Boiled potato | 0.34 | 200 g | 0.68mg |
| Cooked minced beef patty | 0.31 | 125 g | 0.39mg |
| Cooked lentils | 0.18 | 200 g | 0.36mg |
| Banana | 0.18 | 1 fruit (120 g) | 0.22mg |
Contents: ANSES Ciqual 2020 database. Illustrative servings.
A serving of mackerel and a plate of potatoes alone supply around 1.6mg, most daily requirements. Banana, often cited, provides only around 0.2mg per fruit.
3. Some people are more at risk of deficiency
Vitamin B6 deficiency is rare. It causes skin and mucous-membrane lesions (dermatitis, angular cheilitis, inflamed tongue), small-red-cell anaemia, irritability and, in severe cases, seizures. Risk situations are well identified:
- alcohol dependence, malnutrition and obesity;
- chronic kidney failure, especially dialysis;
- autoimmune diseases such as rheumatoid arthritis, which speed up its breakdown;
- malabsorption (coeliac disease, inflammatory bowel disease) and bariatric surgery;
- certain medicines: tuberculosis treatment isoniazid, penicillamine, levodopa and antiepileptics such as valproic acid, carbamazepine or phenytoin.
Smoking is also associated with lower PLP at equal intake. In these situations, a doctor should assess status and the possible value of supplementation.
4. Ten health claims are authorised for vitamin B6
European Regulation No 432/2012 recognises ten claims for foods or supplements that are at least a vitamin B6 “source”. Their exact wording begins “Vitamin B6 contributes…”:
- to normal cysteine synthesis;
- to normal energy-yielding metabolism;
- to normal functioning of the nervous system;
- to normal homocysteine metabolism;
- to normal protein and glycogen metabolism;
- to normal psychological function;
- to normal red blood cell formation;
- to the normal function of the immune system;
- to the reduction of tiredness and fatigue;
- to the regulation of hormonal activity.
Cysteine is a sulphur-containing amino acid found in acetylated form in NAC. Choline also has a homocysteine metabolism claim. These claims describe physiological roles, not disease effects.
What do studies say about mood and premenstrual syndrome?
B6 has been studied far beyond nutritional requirements, with findings requiring caution. In 2022, a double-blind trial assigned 478 young adults to 100mg B6 daily, B12 or placebo for one month. Among 265 assessed for this outcome, reported anxiety decreased in the B6 group, with only a trend for depression. The dose exceeds the current safety limit more than eightfold.
For premenstrual syndrome, a 1999 systematic review (nine trials, 940 women) concluded a probable benefit up to 100mg daily, stressing most trials' poor quality. Yet the neuropathy cases used by EFSA to set its limit were precisely in women followed for this syndrome, taking below 50 to 500mg daily.
Magnesium combined with B6 was also tested in stressed adults; discussed in our comparison of magnesium forms. Other approaches appear in stress and ingredients studied for it.
5. At high doses, vitamin B6 can damage nerves
This is the most important point. Prolonged excess can cause peripheral neuropathy: tingling, burning or numbness, usually in hands and feet, sometimes balance problems. Described since 1983, when seven adults taking massive doses of at least two grams daily developed severe sensory injury, improving after stopping.
Reports then increased with common supplements. In the Netherlands, 191 neuropathy cases after B6 intake were reported between 2007 and 2022. In Australia, the TGA counted 250 reports by late October 2025. Since 2022, a warning is mandatory above 10mg daily. From June 2027, products above 50mg daily will be pharmacist-only, while those above 200mg remain prescription-only.
In 2023, EFSA lowered the adult tolerable upper intake level from 25 to 12mg daily, including pregnancy and breastfeeding. In children, it ranges from 2.2mg in infants to 10.7mg in adolescents. The agency starts from a 50mg threshold and applies a precautionary factor because higher doses cause symptoms sooner.
In France: a maximum of 2mg daily in supplements
The French order of 9 May 2006 limits B6 in supplements to 2mg daily. A ministerial reply published in May 2025 states these maxima have never changed, though the text is under revision. If using several products, add intakes: multivitamins, magnesium–B6 combinations or formulas such as Hexagon® Zen complex, with B6, magnesium bisglycinate, passionflower, L-tryptophan and taurine (up to three capsules daily).
Medicine interactions
At high doses, B6 can interfere with medicines including levodopa, phenobarbital and phenytoin. Conversely, treatments above increase requirements. Tell your doctor or pharmacist about any supplement intake.
Frequently asked questions
Is B6 good for hair?
None of the ten B6 claims concerns hair. In the European register, biotin, zinc and selenium “contribute to the maintenance of normal hair”, and copper to normal pigmentation. Unusual hair loss warrants medical advice rather than random supplementation.
How can you get too much B6?
From food alone, it is very difficult: EFSA says only regular users of high-dose supplements risk exceeding the safety limit. Combining products can be enough. Of 191 Dutch reports, 76 mentioned measured or elevated blood PLP.
What should you do if tingling occurs while taking B6?
Stop the supplement and seek care: this is the Australian agency's label instruction for products above 10mg daily. A doctor can measure blood PLP and investigate other neuropathy causes. In the first 1983 cases, symptoms improved after stopping.
B6 or B12: what is the difference?
These B vitamins share seven claims: energy metabolism, nervous system, homocysteine, psychological function, red blood cells, immune system and fatigue. B6 alone has cysteine synthesis, protein and glycogen metabolism, and hormonal regulation. In the 2022 anxiety trial, B12 produced only trends.
Are vegetarians low in B6?
Not necessarily: pistachios, sunflower seeds, potatoes and pulses supply it. Some plant B6 as glucoside is only half as well absorbed. Vary sources and seek dietary advice for highly restrictive diets.
Can B6 be taken in pregnancy?
Requirements rise slightly to 1.8mg daily according to EFSA, and the 12mg safety limit also applies in pregnancy and breastfeeding. Discuss supplementation with a doctor or midwife.
Conclusion
B6 is a discreet but central coenzyme in over a hundred reactions. A varied diet with fish, meat, potatoes, pulses or nuts easily covers the 1.6 to 1.7mg needed daily. Ten authorised claims describe established roles, but additional intake's value is not demonstrated in well-nourished people. Above all, more is not better: with a safety limit lowered to 12mg and neuropathy reports in several countries, dose vigilance is needed.
Sources
- Commission Regulation (EU) No 432/2012 of 16 May 2012 establishing a list of permitted health claims made on foods. Official Journal of the European Union, L 136, 1-40. eur-lex.europa.eu
- EFSA NDA Panel (2016). Dietary Reference Values for vitamin B6. EFSA Journal, 14(6), 4485. doi:10.2903/j.efsa.2016.4485
- EFSA NDA Panel (2023). Scientific opinion on the tolerable upper intake level for vitamin B6. EFSA Journal, 21(5), 8006. doi:10.2903/j.efsa.2023.8006
- Brown MJ, Daley SF, Beier K (2023). Vitamin B6 Deficiency. StatPearls, NCBI Bookshelf. ncbi.nlm.nih.gov
- ANSES. Ciqual 2020 food composition database. ciqual.anses.fr
- Order of 9 May 2006 on nutrients permitted in food supplement manufacture (Annex III, maximum daily doses). faolex.fao.org
- French National Assembly (2025). Written question No 3441 on revision of the order of 9 May 2006 and ministerial reply (Official Journal, 20 May 2025). assemblee-nationale.fr
- Therapeutic Goods Administration (2025). Medicines containing vitamin B6 (pyridoxine, pyridoxal or pyridoxamine). Safety update. tga.gov.au
- Schaumburg H et al. (1983). Sensory neuropathy from pyridoxine abuse. A new megavitamin syndrome. New England Journal of Medicine, 309(8), 445-448. doi:10.1056/NEJM198308253090801
- Field DT et al. (2022). High-dose Vitamin B6 supplementation reduces anxiety and strengthens visual surround suppression. Human Psychopharmacology, 37(6), e2852. doi:10.1002/hup.2852
- Wyatt KM et al. (1999). Efficacy of vitamin B-6 in the treatment of premenstrual syndrome: systematic review. BMJ, 318(7195), 1375-1381. doi:10.1136/bmj.318.7195.1375
Food supplements do not replace a varied, balanced diet or a healthy lifestyle. Ask a healthcare professional for advice if you are taking medication, pregnant or breastfeeding.
