Vitamin B6

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By Nikola · Precision Nutrition L1 · Updated 5 November 2026

Vitamin B6 is a water-soluble B vitamin that your body turns into pyridoxal 5′-phosphate (PLP), a helper molecule for more than 100 enzyme reactions, most of them in protein metabolism. EFSA sets a population reference intake of 1.7 mg a day for men and 1.6 mg for women, and you get it from fish, poultry, liver, potatoes, bananas, nuts, seeds and pulses. B6 is also the vitamin where more is clearly not better: since 2023, EFSA’s safe upper limit for adults is 12 mg a day, because high-dose supplements can damage nerves.

What vitamin B6 does

“Vitamin B6” covers six related compounds. The active forms work in amino acid metabolism, and PLP also takes part in carbohydrate and fat metabolism. B6 helps make neurotransmitters, keeps blood homocysteine at normal levels, supports the immune system and helps form haemoglobin (NIH ODS).

The EU allows ten health claims for foods that are at least a “source” of vitamin B6 (Regulation (EU) 432/2012). Vitamin B6 contributes to:

• “normal cysteine synthesis” and “normal homocysteine metabolism”
• “normal energy-yielding metabolism” and “normal protein and glycogen metabolism”
• “normal functioning of the nervous system” and “normal psychological function”
• “normal red blood cell formation” and “the normal function of the immune system”
• “the reduction of tiredness and fatigue” and “the regulation of hormonal activity”

They describe what B6 does when you have enough; they are not promises that extra B6 lifts mood or energy.

How much you need a day

Group	EFSA reference intake (PRI)	EFSA upper limit (UL, 2023)	For reference: US RDA / UL (NIH)
Men	1.7 mg	12 mg	1.3 mg (19-50 y), 1.7 mg (51+) / 100 mg
Women	1.6 mg	12 mg	1.3 mg (19-50 y), 1.5 mg (51+) / 100 mg
Pregnancy	1.8 mg	12 mg	1.9 mg / 100 mg
Breastfeeding	1.7 mg	12 mg	2.0 mg / 100 mg
Children 1-17 years	0.6-1.7 mg, by age	3.2-10.7 mg, by age	–

EFSA’s 2016 reference values use a blood PLP level of 30 nmol/L as the marker of adequate status. In 2023 EFSA set the upper limit at 12 mg a day for all adults, including pregnant and breastfeeding women, to protect against peripheral neuropathy, damage to the nerves in the arms and legs. Its starting point was 50 mg a day from a case-control study, divided by an uncertainty factor of 4. The US limit of 100 mg is half of the 200 mg a day that caused no nerve damage in older studies. EFSA concludes that people in the EU are unlikely to exceed its limits, except regular users of high-dose B6 supplements.

Best food sources

Food	Vitamin B6, 100 g	Portion	Vitamin B6 per portion
Pistachios, raw	1.70 mg	28 g (about 49 kernels)	0.48 mg
Beef liver, pan-fried	1.03 mg	85 g	0.88 mg
Sunflower seeds, dry roasted	0.80 mg	28 g	0.23 mg
Atlantic salmon, farmed, cooked	0.65 mg	85 g	0.55 mg
Chicken breast, roasted	0.60 mg	½ breast, 86 g	0.52 mg
Walnuts	0.54 mg	28 g (about 14 halves)	0.15 mg
Banana, raw	0.37 mg	1 medium, 118 g	0.43 mg
Light tuna, canned in water	0.32 mg	85 g	0.27 mg
Potato, baked with skin	0.31 mg	1 medium, 173 g	0.54 mg
Chickpeas, boiled	0.14 mg	1 cup, 164 g	0.23 mg

Source: USDA FoodData Central, SR Legacy, checked 5 November 2026: pistachios FDC 170184, beef liver FDC 168627, sunflower seeds FDC 170563, salmon FDC 175168, chicken breast FDC 171477, walnuts FDC 170187, banana FDC 173944, light tuna FDC 173709, potato FDC 170093, chickpeas FDC 173757. Portions are USDA household measures; values per portion are calculated and rounded.

No single everyday food covers the day, but portions add up fast: 85 g of salmon, a baked potato and a banana together give about 1.5 mg. A handful of pistachios is the strongest snack, ahead of sunflower seeds and walnuts. Boiled chickpeas and canned tuna add smaller amounts. About 75% of the B6 in a mixed diet is absorbed. For a plant-based plate, try a chickpea and sweet potato curry; for fish, baked salmon with root vegetables.

Deficiency: signs and who is at risk

Isolated B6 deficiency is uncommon. When it happens, NIH lists microcytic anaemia (small red blood cells), abnormal brain-wave (EEG) readings, a skin rash with cracks at the corners of the mouth (cheilosis) and a swollen tongue (glossitis), depression, confusion and weaker immune function. A mild deficiency can go without symptoms for months or years.

Groups more likely to run low:

• Kidney disease. Low PLP is common in end-stage and chronic kidney disease, on dialysis and after a kidney transplant.
• Autoimmune and inflammatory conditions. Low levels show up in rheumatoid arthritis, coeliac disease, Crohn’s disease and ulcerative colitis.
• Alcohol dependence. PLP is often very low, partly because a breakdown product of alcohol (acetaldehyde) interferes with making it.

Supplements: when they make sense

The most common supplement form is pyridoxine hydrochloride; some products contain PLP, and absorption is similar across forms (NIH). For most healthy people eating a varied diet, a separate B6 product adds little.

What the research says about popular uses:

• Heart disease. Trials have not shown that B6 lowers the risk of heart attacks or strokes. The HOPE 2 trial did find about 25% fewer strokes, but it combined B6 with B12 and folic acid, so the result cannot be credited to B6 alone.
• Memory and mood. Reviews, including a Cochrane review, found no clear benefit from short-term supplements.
• PMS. A meta-analysis of nine small trials suggested benefit, but the studies were weak, and NIH says more research is needed.
• Nausea in pregnancy. Pyridoxine at 30-75 mg a day reduced nausea in two placebo-controlled trials. The American College of Obstetricians and Gynecologists suggests 10-25 mg three or four times a day. That is above EFSA’s 12 mg limit, so it is treatment for a doctor to prescribe and supervise, not self-care.

Food first. The NHS advises not taking more than 10 mg of B6 a day from supplements unless a doctor advises it. If you take a B-complex, a multivitamin and a magnesium product with added B6 at the same time, add up the B6 from all three labels. We do not recommend specific products on this page.

Who should be careful

• Anyone on high-dose B6. According to the NHS, 200 mg or more a day can cause loss of feeling in the arms and legs (peripheral neuropathy); it usually improves after stopping, but in a few cases, particularly after several months, it can be permanent. The effect of 10-200 mg a day is unclear. NIH describes severe, progressive nerve damage at 1-6 g a day taken for 12-40 months, plus painful skin lesions, sensitivity to sunlight, nausea and heartburn. Tingling or numbness while taking B6 is a reason to stop the supplement and talk to a doctor.
• Epilepsy medicines. Valproic acid, carbamazepine and phenytoin speed up the breakdown of B6. In the other direction, pyridoxine at 200 mg a day may lower blood levels of phenytoin and phenobarbital.
• Cycloserine (a tuberculosis antibiotic) increases B6 loss in urine, and people taking theophylline often have low PLP. Both are for your doctor to manage.
• Food is not the problem. No adverse effects have been reported from B6 in food.

FAQ

What does vitamin B6 do for the body?

Vitamin B6 helps more than 100 enzymes, mostly in protein metabolism. It is needed for making neurotransmitters and red blood cells, for normal homocysteine levels and for the immune system. The EU allows foods that are a source of B6 to say it contributes to normal psychological function and the reduction of tiredness and fatigue.

How much vitamin B6 is too much?

EFSA’s upper limit for adults is 12 mg a day from all sources, set in 2023 to protect against nerve damage. The NHS advises no more than 10 mg a day from supplements unless a doctor recommends more. Nerve damage has been reported at 200 mg a day and above, while no harm has been reported from B6 in food.

Which foods are high in vitamin B6?

Per 100 g, raw pistachios (1.7 mg), beef liver (1.0 mg), sunflower seeds (0.8 mg), salmon (0.65 mg) and chicken breast (0.6 mg) are among the highest (USDA). By portion, a baked potato and a banana each give around 0.4-0.5 mg.

Related entries and articles

• Salmon and canned tuna
• Pistachios, walnuts and sunflower seeds
• Potatoes, bananas and chickpeas
• Vitamin B12 and vitamin B9 (folate) – the other homocysteine vitamins
• Magnesium and vitamin B5 (pantothenic acid)
• Chickpea and sweet potato curry
• Baked salmon with root vegetables
• Foods for energy without caffeine

Sources

1. NIH Office of Dietary Supplements: Vitamin B6, Fact Sheet for Health Professionals, updated 16 June 2023. ods.od.nih.gov
2. EFSA NDA Panel (2016). Dietary Reference Values for vitamin B6. EFSA Journal 4485. efsa.europa.eu
3. EFSA NDA Panel (2023). Scientific opinion on the tolerable upper intake level for vitamin B6. EFSA Journal 21(5):8006. efsa.europa.eu
4. EFSA: Overview on Tolerable Upper Intake Levels, version 11, August 2025. efsa.europa.eu
5. Commission Regulation (EU) No 432/2012 – permitted health claims. legislation.gov.uk
6. NHS: Vitamin B (vitamin B6). nhs.uk
7. USDA FoodData Central, SR Legacy: Nuts, pistachio nuts, raw (FDC 170184); Nuts, walnuts, english (FDC 170187); Seeds, sunflower seed kernels, dry roasted, without salt (FDC 170563). fdc.nal.usda.gov
8. USDA FoodData Central, SR Legacy: Beef, variety meats and by-products, liver, cooked, pan-fried (FDC 168627); Chicken, broilers or fryers, breast, meat only, cooked, roasted (FDC 171477). fdc.nal.usda.gov
9. USDA FoodData Central, SR Legacy: Fish, salmon, Atlantic, farmed, cooked, dry heat (FDC 175168); Fish, tuna, light, canned in water, drained solids (FDC 173709). fdc.nal.usda.gov
10. USDA FoodData Central, SR Legacy: Bananas, raw (FDC 173944); Potatoes, baked, flesh and skin, without salt (FDC 170093); Chickpeas, mature seeds, cooked, boiled, without salt (FDC 173757). fdc.nal.usda.gov

This page is for information only and is not medical or dietary advice.