Indicator Explainer
Vitamin B6
A group of water-soluble vitamins essential for metabolism and normal physiological functions. B6 vitamins, including pyridoxine, pyridoxal, and pyridoxamine, are converted in vivo to pyridoxal phosphate, a cofactor necessary for the synthesis of amino acids, neurotransmitters, and sphingolipids. More than 100 enzymes involved in protein metabolism require vitamin B6 as a cofactor. Vitamin B6 is essential to red blood cell, nervous system, and immune systems functions and helps maintain normal blood glucose levels. Vitamin B6 is found in a wide variety of foods including cereals, beans, meat, poultry, fish, and some fruits and vegetables. (NCI04)
This page explains what the indicator is and how results are interpreted in general terms. Reference ranges depend on the laboratory, the method, and your own situation — no single “normal value” applies to everyone. This page is health information, not a diagnosis. For symptoms, treatment, or urgent concerns, contact a healthcare professional.
When it is tested
Source: National Cancer Institute, NCI Thesaurus 26.09d, C1334. NCI definition, reproduced without modification under CC BY 4.0. Source identity and definition checked automatically on 2026-10-20. No individual clinical interpretation or human reviewer is asserted.
Reading results
Reference intervals and interpretation depend on the laboratory, specimen, method and clinical context. This source definition is educational information; it does not establish a diagnosis, product approval or suitability for an individual.
Also Known As
References
- NCI Thesaurus 26.09d — Vitamin B6 (C1334)
- Source: National Cancer Institute, NCI Thesaurus 26.09d, C1334. NCI definition, reproduced without modification under CC BY 4.0.
- Prevalence and Associations of Abnormal Levels of Vitamin B6 in People with Parkinson's Disease. — Mov Disord Clin Pract, 2026-10-14 (PMID 42872538; literature)
- Vitamin B6 Deficiency and Status Epilepticus: A Preventable Cause of Death in People with Parkinson's Disease. — Mov Disord, 2026-10-14 (PMID 42872523; literature)
- Vitamin B6 Doses on United States Dietary Supplement Labels Relative to the Tolerable Upper Intake Level: A Census of the National Institutes of Health Dietary Supplement Label Database. — Cureus, 2026-10-20 (PMID 42903915; literature)
- Vitamin B6 augments antidepressant activity of venlafaxine by restoring cortical EEG oscillations, behavior and oxidative biomarkers in chronic unpredictable mild stress (CUMS)-induced model of depression-like behavior. — Brain Res, 2026-10-07 (PMID 42843735; literature)
- Plasma biomarkers of vitamin B6 homeostasis and the risk of stroke in individuals with type 2 diabetes: a nested case-control study. — Eur J Nutr, 2026-10-07 (PMID 42841977; literature)
- Vitamin B6 Modification of Bovine Pericardial Bioprosthetic Heart Valve Leaflets Promotes Blood Outgrowth Endothelial Cell Adhesion. — J Biomed Mater Res A, 2026-10-01 (PMID 42865122; literature)