Raymond Shamberger – författare

In recent years many exciting research results have indicated that selen- ium, depending on its concentration, can influence mammalian metabo- lism. It has been estimated that in selenium-deficient areas, selenium or selenium-vitamin E combinations added to animal feed can prevent an- nuallosses to beef and dairy cattle and sheep valued at 545 million dollars and poultry and swine losses valued at 82 million dollars. Some animal diseases that can be prevented by a selenium-supple- mented diet include liver necrosis, nutritional muscular dystrophy, exu- dative diathesis, pancreatic degeneration, mulberry heart disease, infer- tility, growth impairment, periodontal disease, and encephalomalacia. Selenium intake levels are dependent on the plant or animal feed con- centrations, which, in turn, are dependent on the pH of the soil and the types of rocks from which the soils are derived. At normal metabolic levels selenium possesses an antioxidant affect manifested through glutathione peroxidase, and selenium also has an ef- fect on cytochrome P-450 and heme metabolism. Comparisons are made between metabolism of selenium and sulfur in plants, animals, and hu- mans.At greater selenium intake levels acute poisoning occurs when high-selenium-content (10,000 ppm Se) plants are consumed in large quan- tities. The toxic reactions were first manifested in cavalry horses near Fort Randall, Nebraska, in the 1860s.

The importance of environmental factors in the etiology of the major degener­ ative diseases, including cancers, is now generaIly accepted. Evidence obtained from studies with experimental animals and from human populations associates nutritional factors and dietary constituents with the causation of cancers at differ­ ent sites in the body. Estimates by epidemiologists based on comparisons of various population groups have indicated that as much as 50% of the cancer mortality may be influenced by diet. An important indicator is found in migrants to the United States or to other countries who develop the spectrum of cancers typical for the United States (or other countries) but different from that reported for their native country. About 20% of aIl deaths (450,000 per year) in the United States are caused by cancer. In addition, as the population grows the number of cancer cases steadily increases, but the age-adjusted total cancer incidence and mortality rates for sites other than the respiratory tract (cancers primarily attributable to cigarette smoking) have remained stable during the last 30 to 40 years. If one-half of these cancers are associated with dietary practices, an understanding of the process could save about 225,000 lives each year. The causes of cancer have been an important area of cancer research for many years. Certainly if one understands how the diet or the environment affects cancer, great insights might be gained into the mechanisms of cancer as weIl.