Vitamin A in History
Probably the first nutritional deficiency to be clearly recognized was night blindness. The ancient Egyptians, as indicated in the Papyrus Ebers and later in the London Medical Papyrus, recommended that juice squeezed from cooked liver topically applied to the eye to cure night blindness.
This writings date from 1500 BC, but the observations probably are of much earlier origin. The Greeks, who depended heavily on Egyptian medicine, recommended both the ingestion of cooked liver and its topical application as a cure for night blindness, a tradition that has persisted in many societies to his day.
Although interesting references to vitamin A deficiency and their cure can be found throughout history, the modern science of nutrition is only about a century old. The observation that experimental animals lose weight and die on purified diets was noted by many investigations toward the end of the nineteenth century.
In the early part of this century, specific factors necessary for growth and survival were beginning to be identified. Frederick Gowland Hopkins in England, for example, during the period 1906-1912 found that a growth stimulating principle from milk was present in an alcoholic extract of milk rather than in the ash.
During the same period, Stepp in Germany identified one of these “minimal quantitative factors” as a lipid. Soon thereafter, E. V. McCollum and Marquerite Davis in Wisconsin showed that butter or egg yolk, but not lard, contained a lipid soluble factor necessary for the growth of rats. In 1913 they coined the term “fat soluble A” and thereby attributed for the first time the growth stimulating property of these extracts to a single compound.
Approaching the problem is a very different way, Osborne and Mendel at Yale concomitantly found that cod liver oil or butter was an essential growth-promoting food for rats. The year 1913, therefore, was the beginning of the modern age of vitamin A exploration.
Vitamin A in History
