Pure vegetarian diet

DEFICIENCY Pernicious anemia. Conceivably, one could get Bi2 deficiency on a purely vegetarian diet, but this is rare. Deficiency is more likely with diseases of the intestine that impede absorption (e.g., tropical sprue, regional enteritis). The tapeworm Diphyllobothrium latum may deplete Bi2 stores. A deficiency of gastric intrinsic factor (a glycoprotein) may result in Bj2 deficiency, as intrinsic factor is important in facilitating Bj2 absorption in the bowel. Intrinsic factor deficiency may occur following gastrectomy or as an entity in itself, in pernicious anemia. Intrinsic factor deficiency sometimes results from an autoimmune disease. 

The literature contains only one report of a helminthic parasite infesting a human host being apparently favored by improvement in the host s diet. Looss (1911) noted an increased output of hookworm ova when additions of milk and cheese were made to a purely vegetarian diet. Looss had only one human subject (himself), and his observation has never been confirmed. On the contrary, the vast majority of subsequent investigations of a similar nature have indicated that intestinal helminths generally benefit from lack rather than excess of protein in the host s diet. 

NOTE WELL Pure vegetarian diets are not recommended for infants and small children. Also, pure vegetarian diets for pregnant or lactating women should be planned with great care. 

At first, new foods are given in addition to milk feeds and should be in puree form, but as the quantity increases they replace the milk feeds and their nutritional value is of more importance. After 4 months, dietary iron is required and should be introduced as dark green vegetable puree, iron-containing cereals, liver, red meat and (later) egg yolk. Protein quality and protein energy ratio in the solids must be adequate. In the third world and in vegetarian diets, nutritionally adequate mixtures of appropriate local foods are essential. 

Since vitamin Bj2 is found only in animal food, pure vegetarians risk its deficiency over the course of several years. The requirement of vitamin B12 is (with vitamin D) the smallest of all vitamins - only two micrograms per day, with liver stores usually enough to last for five years of deprivation. Vitamin Bj2 participates in DNA synthesis with folic acid. Humans are unable to synthesize folic acid and therefore it is considered a vitamin that must be supplied in the diet. Deficiency of vitamin B 2 or folic acid leads to similar anemia symptoms. There is a separate effect of vitamin Bj2 deficiency on the nervous system. ... 

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