Pharmacological Uses of Folate and Vitamin

The only pharmacological use of vitamin B12, other than for the treatment of deficiency or for rare children with vitamin dependency diseases affecting the binding of the coenzyme to methylmalonyl CoA mutase (Section 10.8.2), is as an antidote for cyanide poisoning. Supplements of vitamin B12 are available for strict vegetarians who might be at risk of deficiency. There is no evidence of any adverse effects of high intakes of vitamin B12. 

Supplements of400 /xg per day of folic acid, begun before conception, halve the risk of neural tube defect (Section 10.9.4), and similar supplements reduce the plasma concentration of homocysteine in people homozygous for the ther-molabile variant of methylene-tetrahydrofolate reductase (Section 10.3.4.2), although it is not known whether or not this will reduce their risk of cardiovascular disease. A number of manufacturers voluntarily enrich foods with folic acid. In the United States and other countries, there is mandatory enrichment of cereal products with folic acid. 

It remains to be seen whether mandatory enrichment of cereal products with folic acid will reduce death from cardiovascular disease. But this, and the widespread voluntary enrichment of foods in other countries, means that intervention studies with folic acid supplements for cancer prevention are unlikely to yield useful results, because the control group will also be receiving a high intake of folic acid. 

Baik HW and Russell RM (1999) Vitamin B12 deficiency in the elderly. Annual Reviews of Nutrition 19,357-77. 

Bailey LB and Gregory JF, 3rd (1999) Folate metabolism and requirements. Journal of Nutrition 129,779-82. 

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