Vitamins
Vitamin B6 (Pyridoxal-5-Phosphate)
Also known as: Pyridoxine · P5P · Pyridoxal phosphate · PLP
Co-factor for 100+ enzymes involved in amino acid metabolism and neurotransmitter synthesis (GABA, serotonin, dopamine). P5P (pyridoxal-5-phosphate) is the bioactive form.
Effective Dose
10–50mg / day
per clinical evidence
Evidence Level
Strong
Vitamins
Mechanism
Aminotransferase and decarboxylase co-factor — amino acid and neurotransmitter metabolism
primary action
Best For
Neurotransmitter synthesis
PMS, Homocysteine reduction, Immune function
This profile is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications.
What Is Vitamin B6 (Pyridoxal-5-Phosphate)?
Vitamin B6 exists as pyridoxine (food/supplement form) and pyridoxal-5-phosphate (PLP, the biologically active co-enzyme form). PLP is required by aminotransferases (transamination of amino acids), decarboxylases (neurotransmitter synthesis), glycogen phosphorylase (muscle glycogen breakdown), and enzymes in haem and antibody synthesis.
How It Works: The Science
PLP acts as a Schiff base intermediate in aminotransferase and decarboxylase reactions. For neurotransmitter synthesis: glutamate decarboxylase (GABA synthesis), aromatic L-amino acid decarboxylase (serotonin, dopamine, epinephrine), and cystathionine beta-synthase (homocysteine → cysteine). PLP is also essential for glycogenolysis via glycogen phosphorylase.
Primary Mechanism
Aminotransferase and decarboxylase co-factor — amino acid and neurotransmitter metabolism
Evidence-Based Benefits
Dosage Guide
Effective Dose
10–50mg / day
RDA: 1.3–1.7mg/day. Supplements commonly provide 10–50mg. P5P (pyridoxal-5-phosphate) is preferred over pyridoxine — already in bioactive form, no liver conversion needed.
Safety Profile & Side Effects
Pyridoxine neuropathy is a real risk above 200mg/day (some cases at >50mg/day with prolonged use) — causes peripheral sensory neuropathy. Keep supplemental doses under 100mg/day unless under medical supervision. P5P may be safer than pyridoxine at equivalent doses.
Who Should (and Shouldn't) Take It
Women with PMS, those with elevated homocysteine, vegans (lower B6 from plant sources), and athletes with high protein intake (increases B6 requirements). Most important as part of a B-complex rather than standalone.
Frequently Asked Questions
Related Ingredients
Medical Disclaimer
Ingredient profiles are for informational purposes only and do not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications. Full disclaimer →