Which of the following statements regarding selenium/selenoproteins is incorrect?

a. They are proven protection against colon cancer.

b. The amount of selenium in foods depends upon the soil where the plants were grown and animals grazed.

c. Selenium functions as an antioxidant.

d. Selenium plays an important role in the regulation of thyroid hormones.

The correct answer is: A. They are proven protection against colon cancer.

Explanation:

Selenium is a mineral that can be incorporated into our bodies in small amounts when we consume certain foods, such as whole grain and dairy products. The amount of selenium in these products depends on the soil where the plants and animals were.

Selenium plays an important role as an antioxidant, which can lower the risk of developing several types of cancer. However, this doesn't mean that its consumption can prevent colon cancer, and the studies that had been done to prove its effectivity in these regards have been inconclusive.

Besides functioning as an antioxidant, selenium also is very important for the regulation of the thyroid hormones, which play an important part in metabolism.