Vitamin B6 is essential for your nervous system, energy metabolism, and immune function. It’s an important vitamin, and getting enough of it matters. But like many things in life, too much isn’t always better.

Taking too much vitamin B6, especially in supplement form, can lead to side effects — and in some cases, even nerve problems. These symptoms are often referred to as vitamin B6 poisoning. This guide explains how much vitamin B6 per day is considered safe, what happens if your dosage is too high, and how to choose the right amount for your needs.

Read all about the benefits of vitamin B6 here: Vitamin B6 benefits

Toxicity threshold for vitamin B6

Vitamin B6 is water-soluble, which means your body can usually flush out what it doesn’t need through urine. But that doesn’t mean you can’t get too much of vitamin B6. With high doses taken consistently, especially from supplements, the body’s ability to eliminate excess B6 can’t keep up. Over time, this may cause toxicity symptoms, mostly affecting the nervous system.

In 2023, the European Food Safety Authority (EFSA) updated its guidance and set a new tolerable upper intake level for adults at 12 mg of vitamin B6 per day [1]. This is a reduction from previous limits and reflects stronger evidence that even moderate excess over longer periods may increase the risk of nerve damage.

One of the most cited studies in this area is by Dalton and Dalton (1987), who reported that women taking around 50 mg of vitamin B6 daily developed symptoms of neuropathy — including tingling, numbness in the hands and feet, and coordination issues [2].

So while 50 mg may sound high, it’s not rare in high-dose B6 supplements, which is why it’s important to know where your intake stands — especially if you’re combining multiple products.

Side effects of vitamin B6 overuse

A 2017 study examined the side effects of high-dose vitamin B6 supplementation and found that pyridoxine – the form most commonly used in supplements – can be particularly harmful.The researchers showed that if your vitamin B6 level is high, especially due to excessive pyridoxine, it may damage nerve cells and block the body’s ability to use the active form of B6, pyridoxal-5’-phosphate (PLP). This can result in a functional deficiency, where B6 is present in the blood but not available to the cells — leading to symptoms of deficiency even with normal blood levels[3].

The vitamin B6 side effects observed in the study develop gradually and are mainly neurological. They tend to appear after several weeks or months of continued use at high doses.

If your vitamin B6 level is high over time, it may lead to imbalance, and in some cases trigger vitamin B6 toxicity or even vitamin B6 poisoning.

Typical signs and side effects of B6 toxicity include:

• Paresthesia: Tingling, burning, or pins-and-needles sensations
• Numbness, especially in fingers or toes
• Balance issues or difficulty walking
• Sensitivity to sunlight
• Nausea or stomach discomfort

Picking the right dosage of vitamin B6

So, lets look more into vitamin B6 – how much per day do we actually need?

For most adults, the recommended dosage for vitamin B6 is:

• 1.4 mg/day for women
• 1.6 mg/day for men

These amounts are enough to support your nervous system, metabolism, and overall health. In some cases — like pregnancy or certain health conditions — a slightly higher intake may be suggested, but always under professional guidance.

It can be confusing to figure out how much vitamin B6 you really need. Interestingly, WHO, the FDA, and EFSA actually agree quite closely on the recommended daily intake. Where things start to differ is the upper limit dosage of vitamin B6 for adults per day.

The table below gives you a quick overview of these recommendations and helps explain where the differences come from:

Comparison of recommended daily intake and upper limit for vitamin B6

Source	Recommended daily dose – Women	Recommended daily dose – Men	Upper limit (UL)	Comment
EFSA (2023)	1.4 mg	1.6 mg	12 mg/day	Lowered UL due to risk of nerve symptoms from long-term high intake
WHO	1.4 mg	1.6 mg	Not established	Recommendations vary slightly depending on age and needs
FDA (USA)	1.3–1.5 mg*	1.3–1.7 mg*	100 mg/day	Much higher UL than EFSA, still often used in clinical settings
Previous EFSA UL	—	—	25 mg/day	Valid until 2023

* FDA values depend on age and life stage:

• Women 19–50 years: 1.3 mg
• Men 19–50 years: 1.3 mg
• Women 51+: 1.5 mg
• Men 51+: 1.7 mg

Vitamin B6 nausea pregnancy dose

Vitamin B6 is often recommended to relieve morning sickness. It’s one of the few supplements with well-documented evidence supporting its use in early pregnancy.

A clinical trial from 1991 studied 59 women in their pregnancy experiencing nausea and vomiting. Half received 25 mg of vitamin B6 three times a day (75 mg daily), while the other half received a placebo. The results showed that women with severe nausea experienced a significantly greater improvement in symptoms when treated with vitamin B6 compared to placebo. The number of women experiencing vomiting also dropped more in the B6 group than in the placebo group [4].

Today, many healthcare providers recommend a lower daily dose, often between 10–25 mg, depending on the severity of symptoms. Vitamin B6 is generally considered safe in pregnancy when used as directed, but it’s always best to consult a doctor before starting any supplement.

Vitamin b6 dosage for weight loss

While there no magical dose of vitamin B6, its not a magic weight loss pill. But it does play a role in metabolism. It helps your body break down carbohydrates, fats, and proteins — and supports neurotransmitters that influence appetite.

Some early research suggests that high-dose vitamin B6 could support fat metabolism. In one study, women with a higher body weight who took 80 mg vitamin B6 daily for 8 weeks saw small but meaningful reductions in fat mass and waist size, along with improvements in insulin balance and appetite-related hormones[5].

Vitamin B6 dosage for sleep

Vitamin B6 is essential for the production of melatonin and serotonin – two compounds that help regulate sleep and mood. Studies have shown that higher B6 intake may be linked to better sleep quality and fewer symptoms of insomnia[6].

New research also suggests that B6 can protect the brain from damage caused by long-term sleep deprivation. It appears to help reduce oxidative stress and support the brain’s natural defense systems – especially in areas linked to memory and learning[7].

You might also like to read: Vitamin B6 in food

Design your vitamin B6 intake strategy

Vitamin B6 plays a role in many areas – from sleep, energy, and mood to pregnancy nausea and weight regulation – which is why it appears in many supplements.

One of our flagship longevity drinks – Rewind Liquid Collagen – contains 15mg Pyridoxal-5-Phosphate (vit. B6) which is close to the recommended upper limit when you take absorption rate into account. With Purovitalis supplements you can be sure you’re getting enough of all major longevity nutrients.

Understanding your vitamin B6 dosage for adults makes it easier to use it wisely — enough to support your needs, without going over the line.

References

1. EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA). (2023). Scientific opinion on the tolerable upper intake level for vitamin B6. EFSA Journal, 21(5), 8006.
2. Dalton, K., & Dalton, M. J. (1987). Characteristics of pyridoxine overdose neuropathy syndrome. Acta Neurologica Scandinavica, 76(1), 8–11.
3. Vrolijk, M. F., Opperhuizen, A., Jansen, E. H. J. M., Hageman, G. J., Bast, A., & Haenen, G. R. M. M. (2017). The vitamin B6 paradox: Supplementation with high concentrations of pyridoxine leads to decreased vitamin B6 function. Toxicology in Vitro, 44, 206–212.
4. Sahakian, V., Rouse, D., Sipes, S., Rose, N., & Niebyl, J. (1991). Vitamin B6 is effective therapy for nausea and vomiting of pregnancy: A randomized, double-blind placebo-controlled study. Obstetrics & Gynecology, 78(1), 33–36.
5. Haidari, F., Mohammadshahi, M., Zarei, M., Haghighizadeh, M. H., & Mirzaee, F. (2021). The Effect of Pyridoxine Hydrochloride Supplementation on Leptin, Adiponectin, Glycemic Indices, and Anthropometric Indices in Obese and Overweight Women. Clinical Nutrition Research, 10(3), 230–242.
6. Peters, L., Fernstrand, A. M., Garssen, J., & Verster, J. C. (2015). The effect of dietary intake of vitamin B6 on sleep quality and insomnia. European Neuropsychopharmacology, 25(S2), 654–655.
7. Yuan, M., Wang, F., Sun, T., Bian, X., Zhang, Y., Guo, C., Yu, L., & Yao, Z. (2024). Vitamin B6 alleviates chronic sleep deprivation-induced hippocampal ferroptosis through CBS/GSH/GPX4 pathway. Biomedicine & Pharmacotherapy, 174, 116547.