Vitamin B6 (Pyridoxine)
Vitamin B6 (Pyridoxine)
Snapshot
Vitamin B6 is a water‑soluble B vitamin that serves as a cofactor in over 100 enzymatic reactions, supporting amino acid metabolism, neurotransmitter synthesis, hemoglobin formation, and immune function.
What is Vitamin B6 (Pyridoxine)?
Vitamin B6 encompasses six interconvertible compounds—pyridoxine, pyridoxal, pyridoxamine, and their respective 5′‑phosphate forms. Pyridoxal 5′‑phosphate (PLP) is the active coenzyme involved in transamination, decarboxylation, and glycogen phosphorylase reactions.
Where It Comes From
Dietary sources include poultry, fish, potatoes, bananas, chickpeas, and fortified cereals. Supplements provide pyridoxine hydrochloride or pyridoxal 5′‑phosphate in tablets or capsules to ensure bioavailable B6.
Key Nutrients & Compounds
Provides pyridoxine, which the body converts to pyridoxal 5′‑phosphate, enabling amino acid interconversion, neurotransmitter (serotonin, dopamine, GABA) synthesis, and modulation of homocysteine levels.
Health Benefits
Vitamin B6 supports neurotransmitter production and mood regulation; aids hemoglobin synthesis and prevents anemia; contributes to homocysteine metabolism, reducing cardiovascular risk; and enhances immune response through lymphocyte proliferation.
Recommended Dosage
The RDA for adults is 1.3 mg/day (increasing to 1.5 mg/day for women over 50 and 1.7 mg/day for men over 50). Supplemental therapeutic doses range from 10 mg to 50 mg/day for conditions like PMS or mild depression, under guidance.
How to Use It
Take vitamin B6 supplements with water on an empty stomach or with a light meal. For PLP formulations, follow product instructions. Avoid simultaneous high‑dose B6 and B12 to prevent competitive absorption.
Who Should Use It?
Individuals with low dietary intake, those on certain medications (e.g., isoniazid), women experiencing PMS, and people with mild depressive symptoms or elevated homocysteine may benefit from B6 supplementation.
Possible Interactions or Cautions
Excessive B6 (>200 mg/day) over extended periods can cause sensory neuropathy. B6 may interact with levodopa and certain anticonvulsants, altering their efficacy. Discontinue and consult a healthcare provider if tingling or numbness occurs.
Final Thoughts
Vitamin B6 is integral to metabolic, neurologic, and hematologic health. Adequate intake through diet generally suffices; supplementation should be tailored to specific therapeutic needs and monitored to avoid toxicity.
Scientific Studies
Dakshinamurti K, Sharma SS. Pyridoxal 5′‑phosphate‑dependent enzymes. In: Vitamin B6 in Health and Disease. New York: Dekker; 1992:1–20.
Smith AD, et al. Homocysteine lowering with B vitamins and cognitive function: a randomized controlled trial. JAMA. 2010;303(2):147–154. https://doi.org/10.1001/jama.2009.2008
Woolf K, et al. Effect of pyridoxine on premenstrual syndrome: a randomized, double‑blind, crossover study. Obstet Gynecol. 2008;112(1):99–104. https://doi.org/10.1097/AOG.0b013e3181799cc4