Vitamin B6

This remarkable nutrient is probably involved in more body processes than any other vitamin or mineral. It's needed to break down and release energy from protein, and is important for the functioning of the nervous and immune systems.

What it is

Vitamin B6, unequivocally the 'workhorse' of nutrients, performs more than a hundred jobs innumerable a day. It functions primarily as a coenzyme, a substance that acts in concert with enzymes to speed up chemical reactions in the cells.

Another name for vitamin B6 is pyridoxine. In supplement form, it is available as pyridoxine hydrochloride or phridoxsl-5-phosphate (P-5-P). Either form satisfies most needs, but some nutritionally oriented doctors prefer P-5-P because it may be better absorbed.

What it does

Forming red blood clots, helping cells to make proteins and brain chemicals (neurotransmitters), such as serotonin, and releasing stored forms of energy – these are just a few of the functions of vitamin B6. There is also evidence that vitamin B6 plays a role in preventing and treating many diseases.

Prevention

Getting enough B6 through the diet or supplements may help prevent heart disease. Working with folic acid and vitamin B12, this vitamin helps the body to process homocysteine, an amino-acid-like compound that has been linked to an increased risk of heart disease and other vascular disorders when large amounts are present in the blood.

Additional benefits

Some women suffering from premenstrual syndrome (PMS) report that vitamin B6 provides relief from many of the symptoms. This beneficial effect is probably due to the vitamin's involvement in reducing excess oestrogen in the body. And its role as a building block for neurotransmitters, vitamin B6 may help to reduce the likelihood of having epileptic seizures, as well as lifting depression. It's estimated that up to 25% of people with depression may be deficiet in vitamin B6.

In addition, the vitamin helps to maintain nerve health. People with diabetes, who are at risk for nerve damage, can also benefit from B6. Furthermore, it helps to ease the symptoms of carpal tunnel syndrome, in which nerves in the wrist become inflamed. For people with asthma, vitamin B6 may reduce the intesity and frequency of attacks. It's especially important for those taking the asthma drug theophylline.

Common uses

  • Helps to prevent cardiovascular disease and strokes.
  • Helps to lift depression.
  • Relieves insomnia.
  • Treats carpal tunnel syndrome.
  • May lessen PMS symptoms.
  • Helps to relieve asthma attacks.

Forms

  • Tablet.
  • Capsule.
  • Liquid.

How much you need

The RDI for vitamin B6 is 0.9-1.4 mg a day for women and 1.3-1.9 mg for men. Therapeutic doses are higher.

If you get too little: Women taking oral contraceptives may have especially low levels of vitamin B6. Mild deficiencies can raise homocysteine levels, increasing the risk of heartand vascular diseases. Early signs of deficiency are skin disorders, such as dermatitis and dandruff, fluid retention and sores around the mouth. Neurological signs include insomnia, depression and, in extreme cases, seizures and brain-wave abnormalities.

If you get too much: High doses of vitamin B6 (more than 2000 mg a day) can cause nerve damage when taken for long periods. In rare cases, prolonged use at lower doses (200-300 mg a day) can have the same consequence. Fortunately, nerve damage is completely reversible once you discontinue the vitamin. If you're using B6 for nerve pain, see your doctor if you experience any new numbness or tingling and stop taking the vitamin. Doses up to 100 mg a day are safe, even for long-term use.

How to take it

Dosage

You can keep homocysteine levels in check with just 3 mg of B6 a day, but a daily dose of 50 mg is often recommended. Higher doses are needed for therapeutic uses. For PMS: Tkae 100 mg of B6 a day. For acute carpal tunnel syndrome: Try 50 m of B6 or P-5-P three times a day. For asthma: Take 50 mg of B6 twice a day.

Guidelines for use

Vitamin B6 is best absorbed in doses of no more than 100 mg at one time. When taking higher doses, gradually increasing your intake will also decrease your chances of nerve damage.

Other sources

Fish, poultry, liver, chickpeas, potatoes, avocadoes and bananas are all good sources of vitamin B6.

Caution

Long-term use of high doses of B6 may cause nerve damage.

Reminder: If you have a medical or psychiatric condition, talk to your health care professional before taking supplements.