Vitamin B6

Also known as: pyridoxine, pyridoxal, pyridoxamine, pyridoxal-5-phosphate, P5P, PLP

Evidence under review. — Not yet rated

Essential B vitamin that supports metabolism, brain function, and immune health. Deficiency causes real harm.

What it does

Vitamin B6 is a water-soluble essential vitamin your body cannot make on its own — you must get it from food or supplements. It plays a central role in breaking down amino acids, carbohydrates,...
Evidence quality

Evidence base hasn't been formally rated yet. See research below.
Clinical dose

1.3–2.0 mg/day (dietary reference intake); therapeutic doses up to 100 mg/day studied for specific conditions
Found in

Thorne Basic Nutrients 2/Day, Nutrilite Double X, Life Extension Two-Per-Day Multivitamin and 17 more

What the Science Says

Vitamin B6 is a water-soluble essential vitamin your body cannot make on its own — you must get it from food or supplements. It plays a central role in breaking down amino acids, carbohydrates, and fats, and is required to produce key neurotransmitters like serotonin, dopamine, and GABA. It also supports immune function and helps the body make hemoglobin. Most adults get enough from food, but supplementation is studied for conditions like PMS, pregnancy nausea, and certain metabolic disorders.

What It Doesn't Do

Won't boost energy if you're not deficient — that's a marketing myth. No solid evidence it builds muscle or burns fat in humans. Animal studies on weight loss don't translate to people. Not proven to treat fibromyalgia — one RCT found it no better than placebo. More B6 is not better; high doses cause nerve damage, not extra benefits.

Evidence-Based Benefits

Prevents B6 deficiency, which causes nerve problems, skin inflammation, and weakened immunity.

Moderate Evidence

Effective at: 1.3–2.0 mg/day

Required for the body to produce serotonin, dopamine, and GABA — key brain chemicals.

Moderate Evidence

Effective at: 1.3–2.0 mg/day

May reduce PMS symptoms like mood changes and bloating in some women.

Weak Evidence

Effective at: 50–100 mg/day

Used clinically to reduce nausea and vomiting in early pregnancy.

Moderate Evidence

Effective at: 10–25 mg up to 3x daily (under medical supervision)

Absorption & Bioavailability

Good — pyridoxine from supplements is well absorbed. The active form pyridoxal-5-phosphate (P5P) is sometimes marketed as superior, but standard pyridoxine converts effectively in healthy individuals.

Red Flags to Watch For

High doses (above 100–200 mg/day long-term) can cause peripheral neuropathy — tingling, numbness, or burning in hands and feet — even without obvious overdose
Nerve damage from B6 toxicity can be irreversible in some cases; regulatory agencies in Australia and Canada have issued formal safety warnings
Many supplements contain far more than the daily requirement (1.3–2 mg); doses of 50–100 mg are common in products despite no proven benefit for non-deficient adults
Pregnant women should not exceed recommended doses without medical supervision — high doses may cause newborn seizures
Photosensitivity (increased sunburn risk) is a documented side effect of high-dose supplementation

What does Vitamin B6 do?

Essential B vitamin that supports metabolism, brain function, and immune health. Deficiency causes real harm.

What is the effective dose of Vitamin B6?

1.3–2.0 mg/day (dietary reference intake); therapeutic doses up to 100 mg/day studied for specific conditions

Is Vitamin B6 safe?

High doses (above 100–200 mg/day long-term) can cause peripheral neuropathy — tingling, numbness, or burning in hands and feet — even without obvious overdose

What doesn't Vitamin B6 do?

Won't boost energy if you're not deficient — that's a marketing myth.

Research Sources

NIH Office of Dietary Supplements
NIH DSLD
Examine.com
Mayo Clinic
WebMD
Web
StatPearls / NCBI Bookshelf

This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-09-27