who carried on similar research at the Lister Institute in
But exactly what are vitamins? At first medical scientists thought they were bio-catalysts, substances that promote chemical reactions in the body without taking a direct part in these reactions. But today it is evident that vitamins often do more than merely aid in chemical reactions. Some of them may actually be substances used structurally by the body.
Of the 13 vitamins usually considered essential for a healthy body, we are most concerned here with the group known as B Complex, and with Vitamins A and C.
In B Complex, we have a number of substances fundamentally necessary for normal health. They are vital for normal metabolism, and are very valuable as "lipotropic" or fat-combatting agents. In addition to helping our bodies handle fats, they also "spark" our hormones and aid in preventing diseases of the nervous system.
Vitamin A, a yellow compound related to substances found in carrots and leafy vegetables, is essential for growth, many bodily functions in the skin and blood vessels, and for resistance against colds and infections.
Vitamin C, which should supplement the diet given in these pages in substantial quantity, is a crystalline substance easily destroyed by cooking. For that reason cooked foods do not provide a very good source of it. It is needed for formation of connective tissue and red blood cells.
A deficiency of this vitamin may be partly responsible for dental caries and infections of the gums, loss of appetite, anemia, and undernutrition.