ABSTRACT
While prevention or treatment of certain conditions such as scurvy and nightblindness had been associated with specific foods for centuries, the association of these conditions with specific chemical substances called vitamins began late in the 19th century and was largely complete by the 1940s. Physicians, biochemists, chemists, and nutritionist identified specific molecules associated with the vitamin deficiency diseases. They were isolated and structurally characterized and their biological functions determined. By the 1950s, commercial production by synthesis or biological preparation made the vitamins widely available and relatively inexpensive. Vitamins are relatively loosely regulated in the United States, with only a minimum content required. On packaged foods the percent of the daily requirement is stated on the basis of a 2000 calorie diet, but the information is required for only vitamins A, C, calcium, and iron. Enriched and fortified products list other nutrients. Since the 1990s, various “dietary supplements” have been exempt from FDA approval, but the FDA can litigate to remove hazardous materials from the market. The effect on vitamin content of food preparation and cooking is an important factor in the level of vitamins obtained through the diet but the information available is limited. In general, measurement of vitamin content is relatively difficult. The huge economic scope of the food production industry has made nutritional labeling and regulation a source of continuing controversy.
