Vitamin B6 is a micronutrient involved in the metabolic process of many enzymes in about ten different metabolic processes, mostly involving amino acids. It is an overall term for a group of related chemical compounds that are interchangeable in these processes. The most common form in the diet is pyridoxal 5'-phosphate. However, most vitamin supplements use the easier to produce pyridoxine.
Vitamin B6 compounds are most common in pork, turkey, beef, bananas, chickpeas, potatoes and pistachios. The recommended intake per day is 2 micrograms. Diet usually provides far more than that as the body easily absorbs the vitamin in the jejunum and the ileum. Any excess is passed in urine.
Cooking, other processing and storage can break down B6 compounds, although the compounds found in plants tend to be more stable.
Patients with a deficiency of the vitamin have flaky, inflamed skin, an inflamed and ulcerous tongue, inflammation of the corners of the mouth, conjunctivitis, inflammation of folds of the skin, sleep disturbances, confusion and neuropathy. It is rare except in the elderly and alcoholics.