Niacin complications

Elucidation of the structure of the B vitamins resxilted in the development of analytical chemical methods. Such methods are useful in industries manufacturing vitamins in which measurements of microgram to milligram quantities are routine, but these same methods are often not applicable to biological fiuids that contain as little as picogram quantities. Colorimetric and fluorometric techniques have been developed for niacin and folate, but these techniques require complicated extraction procedures and blank determinations. They also suflFer from lack of specificity, and the results are often altered by interference from biologically inactive materials that occur naturally or are produced during extraction (16,20). 

The interpretation of the pathogenesis of injuries developing in pellagra is further complicated by the fact that victims of niacin deficiency are also deficient in other vitamins, and pellagra is usually assumed to... 

Deficiencies of various nutrients, primarily vitamins, impair cognition. The link is strongest for vitamin Bj2, thiamine, and niacin. Yet even for these, the role of mild subclinical or multiple deficiencies in the genesis of mental dysfunction is unclear. Most information in this field is based on animal studies often poorly applicable to the human condition or on clinical pathology complicated by advanced age, alcoholism, and intercurrent disease. There is a need for well controlled, double-blind, prospective trials to elucidate the cognitive effects of malnutrition. 

RECOMMENDED DAILY ALLOWANCE OF NIACIN. Estimation of niacin requirements are complicated (1) by the fact that some tryptophan is converted to niacin in man, (2) by the paucity of people of different ages receiving diets varying in niacin and tryptophan content, and (3) by the possible unavailability of niacin in some foods (such as corn). 

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