Recognition that niacin is a vitamin in the early 20th century resulted from efforts to understand and treat a widespread human disease – pellagra.
Pellagra was probably first observed in 1735 in Asturias, autonomous community in Kingdom of Spain.
It was identified among the peasants by Don Gaspar Casal in 1735, soon after the maize was introduced into Europe. A loathsome skin disease, it was called “mal de la rosa” and often mistaken for leprosy.
Pellagra was already an epidemic in Europe in the 18th century, and in the first half of the 20th century it also started its spread in the United States of America, particularly among the poorest social classes.
In 1915, American epidemiologist and US Public Health Service officer Joseph Goldberger conducted a series of experiments on 11 healthy volunteer prisoners in a Mississippi jail and found that he could induce pellagra by altering their diets. He concluded that the disease was caused by the absence of some factor that was lacking in corn. He named it the P-P (for pellagra-preventative) factor.
In 1937, American biochemist Conrad Arnold Elvehjem and his colleagues successfully isolated the vitamin and demonstrated that pure nicotinic acid and nicotinic acid amide would reverse the pellagra and black tongue in dogs by feeding them the Goldberger diet.
He also isolated the P-P factor from active liver extracts, showing that this factor is actually nicotinic acid (subsequently named niacin for nicotinic acid vitamin).
The discovery of niacin as the antipellagra vitamin was announced by C. A. Elvehjem, R. J. Madden, F. M. Strong, and D. W. Woolley in 1937 (J. Am. Chem. Xoc. 59, 1767 (1937)),
During the following year a number of clinical trials were made which established beyond doubt the value of niacin in the treatment of pellagra, and that the acid or its amide should be regarded as the P-P (pellagra-preventive) factor.
Discovery and history of niacin
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