Vitamin B3, also referred to as niacin, is the generic term for nicotinic acid, its amide and their biologically active derivatives. These are essential in all cells for energy production, metabolism and DNA repair. Severe deficiency results in pellagra, which is a combined deficiency. The symptoms of deficiency are primarily dermatitis, diarrhea and dementia. Death results if the condition is untreated.
Human Sciences Research Council (Wed,) studied this question.