2.11f Secrets of vitamin B6 Pyridoxine

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Continues the Chapter on Vitamins - Update 02 Dec. 2021

2.11f: Vitamin B₆ 

Vitamin B₆ comes as: pyridox-ine, -al, and –amine. Pyridoxine hydrochloride is in vitamin pill and food fortification. Wheat bran, sunflower seeds and soybeans are best sources.

Vitamin B₆ helps the conversion of the essential amino acid tryptophan to the B vitamin, niacin, so its deficiency could lead to the niacin deficiency, pellagra. Also B₆ deficiency (and excess) causes peripheral neuropathy (pin & needle feeling and extremity muscle weakness). It protects blood vessel against high cholesterol and the red blood cell against premature destruction.

   Vitamin B₆ is co-enzyme in the synthesis of serotonin and norepinephrine (lack of either believed to be basis for Depression), dopamine (lack involved in Parkinson disease and Huntington chorea, and excess, in Schizophrenia), and gamma-amino-butyric acid (GABA inhibitory neurotransmitter whose lack causes the anxiety symptom and whose excess tranquilizes). This has led to megavitamin B₆ for depression, Parkinson, Huntington, and to treat anxiety. (Ineffective in all cases)

Infant convulsion due to either a genetic condition or to a B₆-deficient diet in pregnant or breast-feeding woman and which requires mega doses pyridoxine to prevent the epileptic fits suggests that B₆ might be good for epileptics.

Homocysteinemia: B₆ is co-enzyme in converting toxic homocysteine to the sulfur-containing essential amino acids. Some persons have partial genetic block that causes homocysteine to pile up in blood and is risk factor for coronary heart disease. The full genetic condition requires 100-500 mg pyridoxine a day plus folic acid. But tests of the vitamin's supplementation have shown no benefit and B6 overdose easily becomes toxic so stick to normal dose vitamin supplement.

Pyridoxine and IQ: Young hyper-homocysteine children with moderately low IQ 57 to 78 were treated with high-dose daily pyridoxine and showed improved IQ.

Requirement: The RDA is easily obtained by eating the usual U.S. diet, but, if in doubt, add sunflower seed or wheat bran. Blood testing for B6 is available. Several years ago, I decided to check my blood vitamin B6 and - Lo! - it showed an abnormally low level although I had not noted deficiency symptoms. But I had been on a strong weight-losing diet and at the time I drank wine daily.  I started taking 40 mg a day supplements (one must be careful of B6 overdose toxicity) and have not noticed a difference in the way I feel. Still, one wants to have a normal blood level of B6.

B₆ and Disease – Megavitamin Use and Toxicity: B₆ has been experimented with as preventive or treatment of Down syndrome, autism, aging, diabetes, carpal tunnel syndrome, premenstrual tension, depression, chronic anxiety, anemia, and local nerve disease. Results are unimpressive. Doses above 200 mg a day over long-term have been reported to cause peripheral neuropathy.

B₆ Depletion in Tuberculosis from INH: Patient with TB may be treated with INH (isoniazid) and since the INH depletes one's vitamin B₆, it is standard practice to give at same time vitamin B₆ supplement to prevent deficiency.  Also, taking a MAOI to reverse depression could cause pyridoxine deficiency so it needs vitamin supplementation.

      Chapter on Vitamins Continues. To read on now, click 2.11g Exciting New Advice on Vitamin B12