Vitamin B6 Requirement

Many people are consuming less than the suggested RDA amounts of vitamin B6 (pyridoxine).  This is due largely to the practice of milling that removes up to 90% of it from grain sources.  As yet, there are no laws requiring the enrichment of milled grains with vitamin B6.

Causes and Development

Probably the biggest cause of deficiency (or an increased requirement) is the addition of antagonists in the environment over the last 50 years.  Antagonists include:

• Hydrazine Compounds: Hydrazine compounds used in medicine INH (isonicotinic acid hydrazine), and hydralazine, high levels of which are found in store-bought mushrooms.  Hydralazine is a medication that is used to treat hypertension and has been linked to a few cases of peripheral neuritis which is associated with pyridoxine deficiency
• Phenelzine is a drug used to treat depression and some people taking it have been found to experience pronounced edema especially in the legs
• Succinic acid 2,2-Dimethylhydrazide is another chemical used in the U.S. and Canada to speed the ripening of fruits.  It is sprayed on such fruits as peaches, nectarines, tomatoes, brussels sprouts, cherries, grapes and apples.  Residues remain on these fruits after harvesting.  This can be avoided by eating only organic produce
• Maleic hydrazide is another derivative of hydrazine used in agriculture as a plant growth inhibitor and herbicide (potato chips have particularly high levels maleic hydrazide with as high as 25mg per 6oz bag of chips).  Once again, choose the organic alternatives
• Antioxidants in the petroleum industry and plating materials and anti-tarnish agents used in metal manufacturing
• Tartrazine (yellow dye #5): From 1949-1970 nearly 1 million pounds per year were used in foods and medications
• Peroxides and free radicals found in abundance in our food supply as oxidized fats.  Foods such as barbecued foods, fried foods, potato and corn chips, and all foods processed with fats or oils which includes most restaurant-prepared foods
• Birth Control Pills are well known B6 antagonists.  15-20% of women on oral contraceptives show deficient levels of pyridoxine on tryptophan load tests and many suffer deficiency symptoms.  It should be noted that 10-30mg per day of vitamin B6 corrected both the load test and relieved the symptoms in most of these women
• PCBs (polychlorinated biphenyls): Although they have been banned, there are still incredible amounts in the environment.  They have been found in 99% of all Americans tested and 100% of all Canadians.  Fish taken from contaminated waters are the primary source of PCBs.  In 1975, 69% of all breast milk tested positive and in Michigan and of more than 1000 women tested, 100% were positive
• Environmental toxins: Jet or rocket fuel produces hydrazines that can persist for weeks after their production.  Tobacco smoke contains significant amounts as well as the tobacco itself thus chewing tobacco will increase the need for more B6.  One study on the birth weight of newborns showed that the normal growth inhibition that occurs with exposure in utero to tobacco smoke could be inhibited with the addition of 15mg of B6 per day
• L-canavanine: compound found in alfalfa sprouts
• Other non-hydrazine medications that act as pyridoxine antagonists include penicillamine and cycloserine
• Alcohol has been shown to deplete B6 stores
• Caramel coloring acts as an antagonist to B6 and has been found to prevent B6 from entering into the brain.  Caramel coloring is produced by the heating up of certain sugars
• Other foods that contain lysine (an essential amino acid found in many foods) that have been processed with heat have been found to antagonize B6

Other causes include:

• Pregnancy: Up to 50% of pregnant women may suffer vitamin B6 deficiencies on normal diets according to tryptophan load test studies.  It is known that B6 is actively transported to the fetus and concentrated up to 4 times the normal level
• Malabsorption: Celiac disease, Crohn's disease, etc.
• Age-related: several studies of Danes and Americans showed low B6 status corresponding to age.

Signs and Symptoms

Deficiency symptoms include pain and stiffness in arms and hands, painful 'knots' on the last joints of the fingers, headaches, bad breath, dizziness, extreme nervousness, foul-smelling flatulence, burning pain and cramps in abdomen, lethargy, dizziness, swollen ankles, an itching red rash around genitals, nausea, sore lips, mouth and tongue, and "showers of dandruff".

Severe B6 depletion may result in depression, nausea, vomiting, mucous membrane lesions, seborrheic dermatitis, peripheral neuritis, ataxia, hyperacusis, hyperirritability, altered mobility and alertness, abnormal head movements and convulsions.