Vitamin B6

B6 occurs in three forms - pyridoxine, pyridoxamine and pyridoxal. It is water soluble and is usually excreted about eight hours after entering the body. Like most other B complex vitamins it needs daily replacement. An American, Professor Paul Gyorgy, isolated it from liver in 1934.

Today, however, scientific understanding of B6 remains comparatively limited. There are many unknown factors in its make-up and numerous unproven theories about its effect on the human body.

• It aids the metabolism of protein and is essential for the production of antibodies and red blood cells.
• It is also necessary for the maintenance of the delicate chemical balance of the brain.
• It helps convert the amino acid tryptophan to niacin.
• It helps muscles to function normally.

Important

• Fish, liver, meat (100g serving)
• Nuts, especially walnuts and hazlenuts (50g serving)
• Fruit - banana (100g serving), avocado pear (150g / 1/2 serving), dried fruits (40 serving)
• Yeast products e.g. Vegemite/Marmite (3g serving)
• Vegetables - broccoli, Brussels sprouts, cabbage, cauliflower, spinach, peas, corn, carrots (50-100g serving), potatoes (120g serving)
• Dairy products - full cream/skim milk, yoghurt (250m 1 serving)
• Cereals-wholemeal bread (4 slices), bran (10g serving)

Moderate

• Egg (1)
• Cheese (25g serving)
• White bread (4 slices)
• Fresh fruit - citrus, stone and berry fruits, apples (100g serving)

Low or Nil

• Fats and oils

B6 (as pyridoxamine and pyridoxal) can be destroyed by heat, light and oxygen in the air. Heat has no effect on B6 in its pyridoxine form.

Like the other water soluble vitamins, B6 is extracted from food by the water in which it is cooked - with the vitamin remaining, in dissolved form, in the cooking water which is too often discarded. The vitamin is also lost in drips from thawing frozen foods.

Long storage on the supermarket shelf or in the kitchen cupboard is not helpful either.

Alcohol is a natural enemy of B6, just as it is for most B complex vitamins.

In adults skin complaints, anemia and emotional imbalance can be the result of B6 deficiency.

There are theories that lack of B6 can also cause an increase in the body's production of oxalic acid leading to kidney and gallstones. Serious deficiency can cause convulsions in babies.

This was discovered almost by accident when there seemed to be almost an epidemic of epileptic babies in the USA during the early 1950s. The babies did not respond to standard treatments. Finally the doctors found a common factor among all the babies - they were being fed the same liquid baby food formula. On testing the formula it was found to be very low in B6.

The convulsions ceased once the babies received their normal required amount of B6.

The Australian recommended daily allowance, related to protein intake, for healthy adults is approximately 1.4 milligrams depending on age.

The requirement is increased for people on a high protein diet.

It has been used to combat a variety of medical problems including "morning sickness" during pregnancy, anemia, motion sickness, skin disorders, depression and premenstrual tension.

However, the effectiveness of supplementary B6 treatment is the subject of much conjecture and theorizing. There is little hard scientific evidence.

It is suspected that a very high dosage of B6 taken on a regular basis can be addictive.

Megadoses of 86 (2-6g/day) for long periods have been reported to produce numbness in hands and feet and clumsiness of movement.