Nicotinic Acid Deficiency (Archived)

Excerpt

Niacin (vitamin B), also known as nicotinamide or nicotinic acid, is an essential water-soluble vitamin. It is important for the metabolism of macronutrients (carbohydrate, protein, and fat) due to being part of the NAD (nicotinamide adenine dinucleotide) and NADP (nicotinamide adenine dinucleotide phosphate) coenzymes. It is mainly found in protein-rich foods (e.g., cereals, legumes, meat, and milk) and yeast. The former food sources are high in tryptophan, which can be converted into niacin in the liver (60 mg tryptophan is needed to produce 1 mg niacin). The recommended daily allowances for niacin is 2 to 4 mg for infants, 6 to 8 mg for children, 12 mg for teenagers, 16 mg for men, 14 mg for women, and 17 and 18 mg for lactating and pregnant women, respectively.

Dietary deficiency of niacin results in pellagra. Pellagra was first described 250 years ago by the Spanish physician Don Gaspar Casal in 1763. It is characterized by dermatitis, diarrhea, dementia, and eventually death if not treated by giving niacin. This is why it is called the 3 D syndrome, or 4 Ds disease. However, diarrhea and dementia may not always be present. Recent studies also revealed that niacin deficiency might be associated with Alzheimer, Parkinson, Huntington diseases, cognitive impairment, or schizophrenia. Early diagnosis and treatment are crucial.