hey cheer this next tidbit is interesting, although it doesn't reference its sources. i haven't read about cadmium interactions with zinc before - would be interesting to follow up on this.
http://www.tvernonlac.com/cadmium.html
Quote:
The toxic metal [cadmium] strongly displaces zinc from its proper sites in the body. It replaces zinc in the arteries causing stiffness, inflammation and high blood pressure. High cadmium and low zinc in the arteries can promote aneurysms. It is stored in the body in place of zinc. Many symptoms of cadmium poisoning are the same as those of zinc deficiency such as decreased appetite, dry scaly skin, loss of hair, loss of body weight, decreased body temperature, decreased growth, immune suppression, reduced testosterone activity and impotence, prostate cancer, loss of sense of smell, and copper toxicity. Cadmium is associated with cancer, diabetes, cardiovascular disease, and many other major degenerative diseases. It's ability to replace zinc is an important reason for this. Zinc is required for over one hundred critical enzymes. Zinc is essential for insulin production, insulin release and it prolongs the action of insulin. Cadmium and copper toxicity are frequently involved in glucose tolerance problems such as hypoglycemia and diabetes.
The toxic effects of cadmium are kept under control in the body and brain by the presence of zinc, [its] primary antagonist. Zinc is very protective against cadmium absorption in the intestines. The increasing prevalence of zinc deficiency increases toxic metal retention and the toxic effects. Refining flour and sugar removes most of the zinc, chromium and selenium. Refined grains including rice and frozen vegetables, promote zinc deficiency due to the low levels in the food and refined sugars and carbohydrates increase the demand for zinc. Sugar from any source including fruits and fruit juices, causes zinc depletion. Whole wheat has a cadmium/zinc ratio of about 1 to 120. White, refined wheat flour has a cadmium/zinc ratio of about 1 to 12. Eating mostly refined foods is a major source of toxicity due to the effect on this ratio. The ideal hair tissue mineral ratio is 1 to 500. Higher levels of protein, iron, calcium and manganese also have a protective effect.
Smoking cigarettes is the worst source of toxicity as it is the primary metal found in cured tobacco. It is sprayed on the tobacco plant as a fungicide. It is also present in the cigarette papers. In each cigarette the residual cadmium concentration averages 1.4 micrograms. Passive smoke also contains substantial amounts. One pack of cigarettes deposits at least 4 mcg into the lungs which is ten times the amount that the body can assimilate and excrete in a day. It will be retained in the kidneys, blood vessels, brain and lungs. It weakens the immune system and gives rise to the typical smoker’s diseases: lung infections, lung cancer, emphysema, heart disease, and malignant tumors.