Vitamin B6 Overview
Vitamin B6 is water-soluble and is part of the Vitamin B complex group. The seven forms of vitamin B6 are:
- Pyridoxine (PN), this form is most common in vitamin B6 supplements
- Pyridoxine 5’-phosphate (PNP)
- Pyridoxal (PL)
- Pyridoxal 5’-phosphate (PLP), the metabolically active form which is sold as ‘P-5-P’ vitamin supplement
- Pyridoxamine (PM)
- Pyridoxamine 5’-phosphate (PMP)
- 4-Pyridoxic acid (PA), the catabolite which is excreted in urine
The main role for vitamin B6 is to act as a coenzyme to other enzymes in the body that are specifically involved in metabolism. This role is performed the active Vitamin B6form, pyridoxal phosphate. The active form of pyridoxal phosphate can be converted into other natural forms like pyridoxal, pyridoxine (found in B6 supplements), and pyridoxamine which are found in food.
Why do we need Vitamin B6?
The above forms of vitamin B6, especially pyridoxine, are needed by the body for the proper function of sugars, fats, and proteins. It is also necessary for proper growth and development of the brain, nerves, skin, and other parts of the body. Vitamin B6 plays an important role in the body's metabolic processes like:
- amino acid, glucose and lipid metabolism
- neurotransmitter synthesis
- histamine synthesis
- haemoglobin synthesis and function
- gene expression
Vitamin B6 is necessary for maintaining healthy blood cell metabolism, the nervous system, immune system, and other body functions. A deficiency of vitamin B6 can lead to problems like skin inflammation (dermatitis), depression, anaemia, and heart disease.
Vitamin B6 food sources
Vitamin B6 can either be taken through vitamin B6 supplements or through foods like:
- vegetables
- bananas
- pistachios
- hazelnuts
- garlic
- liver
- fish (tuna, salmon, cod)
- sunflower and sesame seeds
- lean pork
- molasses
Depending on the cooking, storing, and processing conditions of these foods, vitamin B6 may be more or less than 50%. Plant foods are less likely to lose their vitamin B6 content after processing because they contain a form of B6 (pyridoxine) which is far more stable than the B6 forms (pyridoxal or pyridoxamine) found in animal foods. One such example is milk. It can lose up to 30% or 70% of its vitamin B6 content once it's dried. Another example is grains. Vitamin B6 is found in the germ and aleurone layer of the seed. Milling and refining into white flour results in a reduction of vitamin B6. Freezing, canning, and other food processing methods can also lead to a loss of vitamin B6 in these foods.