It is widely distributed in nature: oyster, seafood, and grains are rich sources; it also can be obtained from air and the water supply.
About 6% of the cadmium ingested in food and beverages is absorbed by the human body. Higher dietary levels of calcium and protein need to increase cadmium absorption.
Most of the absorbed cadmium is retained in the kidneys bound to a metal-binding, high sulfhydryl protein, metallothionein.
The essentiality of cadmium in humans remains to be established. Nutritional requirements, if they exist, are very low and easily met by the levels in food and drinks.
There was a study that regular high doses of cadmium caused increased blood pressure, with pressure returning to normal when the cadmium treatment ceased.
Study also found elevated cadmium levels associated with atherosclerosis, an increase in heart size and reduced kidney function.
Cadmium in human diet
