Pellagra, << puh LAG ruh or puh LAY gruh, >> is a disease caused by a lack of niacin and other B-complex vitamins (see Vitamin (Water-soluble vitamins ) ). This disease became widespread after the Spaniards introduced corn into Europe from Central America in the early 1700’s. Corn is a poor source of niacin, and many people who ate corn as the main part of their diets developed pellagra. For more than 200 years, pellagra was common in areas of the world where people ate mostly corn. In the early 1900’s, the American physician Joseph Goldberger proved that pellagra was associated with the diet (see Goldberger, Joseph ).
Today, pellagra occurs chiefly in developing nations where corn and corn products are the major food source. It also may affect people who do not have a proper diet, especially the poor and people dependent on alcohol or drugs.
Early symptoms of pellagra include weakness, lack of appetite, diarrhea, and indigestion. Dermatitis (skin inflammation) develops especially on parts of the body exposed to sunlight, heat, friction, or other irritants. The tongue becomes swollen and sore, and lesions (skin eruptions) develop in and around the mouth. Later symptoms of pellagra include anxiety, headaches, irritability, and sleeplessness. In extreme cases, severe psychosis may develop.
Pellagra is treated by changing the diet so that it includes a sufficient amount of protein-rich foods, such as meat, fish, eggs, and milk and milk products. These foods are good sources of niacin or of the amino acid tryptophan, which the body converts into niacin. In some cases, physicians prescribe niacin tablets for patients with pellagra.
