Your uncle Carlos has survived two heart attacks, and recently asked if he might be deficient in selenium, which he had just heard is essential to heart health. You are aware of his food habits and explain that his condition could not be the result of a dietary deficiency of selenium because
tap water is a source of selenium.
selenium is prevalent in most food groups.
he consumes legumes, a rich source of selenium.
he drinks fluoridated water, which increases bioavailability of selenium.