Vitamin B -- nicotinic acid

Deficiency of nicotinic acid (also known as niacin), one of the B-complex vitamins, causes pellagra.</P> Pellagra was known as the 'disease of the four D's' -- dermatitis, diarrhea, dementia and death.

The disease is specifically characterized by:</P> > >Dermatitis: A rash on areas of the skin exposed to light or trauma and ulcerations within the mouth >Diarrhea >Dementia: Mental disorientation, confusion, delusions and depression >Death, if untreated.</LI></UL> Pellagra, once a puzzle, was solved by Joseph Goldberger (1874-1929).

Serving in the Public Health Service, Dr.

Goldberger proposed that pellagra was due to a nutritional deficiency and in 1915 began experiments with Mississippi prison inmates (who 'volunteered' in return for full pardons).

Dr.

Goldberger fed them a poor diet he believed caused pellagra and within months, many developed the disease.

Their symptoms of pellagra were reversed when meat, fresh vegetables and milk were added to their diet.</P> Niacin, Dr.

Goldberger subsequently showed, was the principle that had this remarkable effect.

A readily-available B vitamin, niacin cures pellagra and prevents it.</P> The name 'pellagra' comes from the Italian 'pelle', skin + 'agra', rough = rough skin, referring to the skin problems in pellagra.