VITAMIN B1 (THIAMIN)

  Vitamin B1, or thiamin, is associated with the proper functioning of the nervous system. It is an essential part of an enzyme in the human body which is necessary for the complete and proper oxidation of sugar. It seems probable that the several signs of thiamin deficiency—impaired functioning of the nervous system, loss of appetite, loss of muscle tone, particularly in the intestines, loss of weight, a slowing of the heart rate, and occurrence of pains and weakness in the limbs in severe cases—are probably results of disordered and incomplete oxidation of sugar in the body. A disease known as beri-beri, associated with severe polyneuritis, final loss of nervous and muscular control, and heart failure (as ultimate cause of death), not uncommon in oriental countries, is a specific vitamin B1 deficiency disease. In this country, the symptoms of vitamin B1 or thiamin deficiency are generally comparatively mild, but nevertheless they are important enough to be considered and avoided.

  Vitamin B1 is widely distributed in natural foods, both in the animal and plant kingdoms, and important sources are: yeast, soy beans, whole grains (germs and outer layer of seeds), pork, liver, other organs of animals, muscle meats of many animals, peanuts, egg yolk, legumes, and many vegetables. Although it is present in foods, it may be lost to a considerable extent in the cooking process unless cooking is done with care, and the cooking waters are retained and used in soups or gravies.

VITAMIN B2 (RIBOFLAVIN)

  Specifically, lack of adequate riboflavin in the dietary is characterized by cessation of growth, and a specific skin disorder which results in lesions of the lips, cracks at the angles of the mouth and greasy accumulations at the angles of the nose. According to several investigators, if the person is deficient in riboflavin there are also certain abnormal changes in the eye, in the form of invasion of the cornea by loops of capillaries. A general failure in nutritional well-being, digestive disturbances, nervous depression, increased suspectibility to infection and diminished vitality are nonspecific but often observed, if the supply of riboflavin is inadequate.

  Riboflavin is widely distributed in the plant and animal kingdoms, particularly in yeast, milk, liver, beef heart, and beef kidney. Beet greens, turnip greens, mackerel, and oysters also afford notable quantities of this nutrient.

NIACIN

  Niacin is a constituent of certain co-enzymes which are essential in tissue respiration. It prevents the specific deficiency disease, pellagra, which is characterized by skin eruption (dermatitis), affecting especially the backs of the hands and forearms, face, neck, and feet; digestive disturbances (diarrhea); and nervous disorders. The severity of the disease is increased by exposure to sunshine.

  Important natural sources of niacin are beef, liver, pig liver and kidney, all kinds of lean meat and poultry, salmon, wheat kernel and bran, peanuts, peanut butter, brown rice, whole wheat, and yeast.