Selenium's physical and
chemical properties resemble sulfur. The highest concentrations of selenium are
found in the kidney, liver, heart, and spleen. As selenium is absorbed it is
deposited in all bodily tissue with the exception of fat tissue. Normal blood
concentration level of selenium is 0.22mcg/100ml.
Functions
A trace mineral that can function either alone or as part of
an enzyme system. Selenium is able to mimic vitamin E in some of its
antioxidant functions such as protecting cells, mitochondria, microsome,
and lysosome membranes from lipid peroxidation damage. It and vitamin E
are not able to replace each other, but are involved in some of the same
systems in which the results end up being the same. Some of selenium's
other functions include destroying hydrogen peroxide as a cofactor with glutathione
peroxidase, a component of sulfur amino acid metabolism, binding to heavy
metals and perhaps lowering toxicity in cases of mercury poisoning, cancer
prevention, cardiac disorder prevention, and normal development of the
unborn fetus.
Deficiency can cause
Cardiomyopathy, myocardial death, increased risk of cancer, compromised
immune function, reduced glutathione peroxidase activity, and impaired
antioxidant defenses.
Toxicity symptoms include
Possible interference with sulfur metabolism, impaired
embryonic development, abnormal bone and cartilage development, blindness,
salivation, muscle paralysis, abdominal pain, respiratory failure, liver
disease, cardiomyopathy.
Food Sources
Liver, kidney, meats, and seafood. Grains and vegetables
depending on soil levels of selenium. Brazil nuts, brewer's yeast,
broccoli, brown rice, chicken, dairy products, dulse, garlic, kelp,
molasses, onions, salmon, torula yeast, and wheat germ.
