Vitamin B6, or Pyridoxine, is a group of six related compounds: pyridoxal, pyridoxine, pyridoxamine, pyridoxal 5'-phosphate, pyridoxine 5'-phosphate, and pyridoxamine 5'-phosphate. Although these forms function like pyridoxine, their bioavailability differs.
Our nervous and immune system needs Vitamin B6 to function efficiently. Vitamin B6 is important for energy production, healthy skin, muscles, and blood. It has similar characteristics to Vitamin B1, B2 and B3.
Vitamin B6 is important for carbohydrate and protein metabolism, blood glucose regulation and the breakdown of glycogen, the production of haemoglobin and antibodies, the formation of hormones and neurotransmitters, as well as the activation of Vitamin B3. Many of these functions are supported by Vitamin B2, B9, and B12.
Vitamin B6 maintains our nervous and immune system and promotes healthy skin and muscles.
Fluctuating blood sugar levels often cause ups and downs in mood and energy. Vitamin B6 helps to maintain normal blood sugar levels; it helps our blood to carry oxygen and to breakdown glycogen.
Possible uses include:
A deficiency is rare with today's food fortification but can still occur, in particular from drug interactions or underlying medical conditions of the digestive system. Smokers and women taking oral contraceptives are at a higher risk of Vitamin B6 deficiency.
High alcohol or coffee consumption but also high protein diets may require more Vitamin B6. Furthermore, Pyridoxine blood levels tend to decline with age.
Deficiency symptoms include:
Although Vitamin B6 is a water-soluble Vitamin and excess amounts are easily excreted, toxicity is a concern and too much Vitamin B6 can result in nerve damage to the arms and legs.
Adverse effects may include:
Vitamin B6 is stable to heat but is very easily destroyed by light. Cooking and food processing can destroy a significant portion of Vitamin B6. Food drying, freezing and canning can also reduce its content.
Dietary sources include:
The Dietary Reference Intakes (DRIs) for Vitamin B6, developed by the Food and Nutrition Board (FNB) at the Institute of Medicine of The National Academies, currently state 1.3mg for adult men and women up to the age of 50 years, after which the amount increases to 1.7mg for adult men and 1.5mg for adult women. The Tolerable Upper Intake Level for Vitamin B6 is 100mg. Australia and New Zealand adapted the same values as their Nutrient Reference Values (NRVs) but only allow for a Tolerable Upper Intake Level of 50mg.