One of the major diseases that vitamin deficiencies were causing in the U.S. was once pellagra. Characterized by ugly red blotches on the skin, digestive disorders and delirium, pellagra killed 10,000 persons a year in
the Southern States alone just before World War I. The disease struck only the poor, and at first it was thought to be infectious. Vitamin deficiencies being unknown, scientists thought that the only remedy was a diet rich in meat, milk or eggs, the very items the poor could least afford.
But in 1938 it was shown that nicotinic acid, or niacine, could cure pellagra as well as prevent it. Later, when scientists discovered vitamins and vitamin deficiencies, bread, flour, cornmeal, macaroni and white rice were enriched with niacine, as well as other vitamins in the vitamin B complex, and iron. Thus, pellagra was no longer a threat in Western countries.
Blindness, anemia, goiter also caused
by vitamin deficiencies
There are other vitamin deficiencies which can cause various deficiency diseases: blindness from lack of vitamin A, still found in Africa and the Far East; anemia from lack of iron, most common in children and in women of childbearing age; goiter from iodine deficiency. Scientists kept identifying new essential nutrients whose lack may cause damage, or discovering that previously unexplained deformities, such as one form of dwarfism, may be caused by a dietary deficiency of some mineral such as zinc.
The doctor of the future will give no medication,
but will interest his patients in the care of the
human frame, diet and in the cause and prevention
of disease. (Thomas Edison)
Most of the classic deficiency diseases, however, have disappeared from the affluent world. They began disappearing even before nutritionists had defined the relationships between certain chemicals and health. As standards of living rose in Europe and North America, people ate not only more food, but a wider variety of foods, helping to ensure better-balanced diets.
This together with more recent nutritional and medical knowledge, has been largely responsible for the increasing size of children in the Western countries. A similar increase in height has also been taking place in the second part of the 20th century among Japanese children, as that country's standard of living rose.