The Benefits of Vitamin B6 (pyridoxine)
By: Dr. Obikoya
Vitamin B6 is a water soluble vitamin that is important in
protein metabolism and the function of a number of enzymes in the body. It
promotes healthy skin, is essential for maintaining a healthy nervous system and
also for the formation of hemoglobin in red blood cells and antibodies that help
fight infection. Vitamin B6 It occurs in three forms: pyridoxine (or pyridoxol),
pyridoxal, and pyridoxamine. It is often used to supplement diet in the
pre-menstrual part of the cycle.
Pyridoxine was first isolated in 1938 and synthesized in 1939. Pyridoxal and
pyridoxamine, which were discovered in the 1940s, are responsible for most of
the vitamin B6 activity in organisms.
Vitamin B6 is active in its coenzyme form of pyridoxol phosphate and functions
in the formation and breakdown of amino acids, and hence indirectly of protein,
in our body. It is also involved in the synthesis of serotonin and
norepinephrine (two neurotransmitters) and of heme (a molecular constituent of
hemoglobin).
No human disease has been found to be caused by a deficiency of vitamin B6 in
the diet, although certain human ailments of obscure origin respond to its
administration. In experimental animals, vitamin B6 deficiency produces symptoms
that depend to some extent on the other constituents of our diet. Anemia; dry,
cracked lips; red and inflamed tongue; sensation of burning skin can, however,
occur as a result of vitamin B6 deficiency.
About 1950 vitamin B6 deficiency was produced experimentally in human infants.
In infants the deficiency first manifests itself in a convulsion that is readily
controlled by administration of the vitamin. Many cases of such convulsions have
been reported in infants fed a human-milk substitute with insufficient amounts
of vitamin B6. Because heat treatment of cows' milk destroys the vitamin, the
deficiency can be corrected by altering the processing of the milk. An adult
human needs 2.0 to 2.2 mg of vitamin B6 daily.
We all need regular intake of vitamin B6, but more especially women taking the
combined contraceptive pill, older people (over 55), vegetarians and vegans and
those who consume large amounts of alcohol.
Vitamin B6 plays a major role in making proteins, hormones, and
neurotransmitters (chemicals that carry signals between nerve cells). Because
mild deficiency of vitamin B6 is common, this is one vitamin that is probably
worth taking as insurance.
Theres good evidence that adequate intake of vitamin B6 can help prevent
heart disease and reduce the nausea of morning sickness. There is a connection
between heart disease and low levels of vitamin B6. People with the high vitamin
B6 levels are about 30% less likely to develop heart disease than those with the
low vitamin B6 levels. Vitamin B6 may help the heart in several ways.
Preliminary studies suggest that it can reduce the tendency of platelets in the
blood to form clots, and also lower blood pressure to some extent.
Vitamin B6 Vitamin B6 supplements have been used for years by conventional
physicians as a treatment for morning sickness. It is also widely recommended
for premenstrual syndrome (PMS) and asthma. When combined with magnesium,
vitamin B6 may be helpful for autism.
Vitamin B6 is safe to take up to 100mg per day on a long term basis, although
high levels of up to 200mg have not been shown to cause problems. 100mg of
Vitamin B6 in long term usage and 200mg in short term usage are upper safe
levels. However, at higher dosages (especially above 2 g daily) there is a very
real risk of nerve damage.
Vitamin B6 requirements increase with age. The U.S. Dietary Reference Intake
(formerly known as the Recommended Dietary Allowance) is as follows:
Infants 05 months, 0.1 mg
611 months, 0.3 mg
Children 13 years, 0.5 mg
48 years, 0.6 mg
913 years, 1.0 mg
Males 1450 years, 1.3 mg
51 years and older, 1.7 mg
Females 1418 years, 1.2 mg
1950 years, 1.3 mg
51 years and older, 1.5 mg
Pregnant women, 1.9 mg
Nursing women, 2.0 mg
Severe deficiencies of vitamin B6 are rare, but mild deficiencies are extremely
common. In a survey of 11,658 adults, 71% of men and 90% of women were found to
have diets deficient in B6.1 Vitamin B6 is the most commonly deficient
water-soluble vitamin in the elderly,2 and children, too, don't get enough.3
References
1. Kant AK and Block G. Dietary vitamin B6 intake and food sources in the U.S.
population: NHANES II, 197680. Am J Clin Nutr 52: 707716, 1990.
2. van der Wielen, et al. Dietary intake of water soluble vitamins in elderly
people living in a Western society (19801993). Nutr Res 14(4): 605638,
1994.
3. Albertson AM, et al. Nutrient intakes of 2- to 10-year-old American children:
10 year trends. J Am Diet Assoc 92(12):14921496, 1992.