Nutrients that are necessary for health and cannot be synthesized by human cells are called essential.

Diuretics cause weight reduction by

Niacin can be synthesized in human cells from the essential amino acid called tryptophan.

Obesity is defined as the presence of excessive adipose tissue.

Dietary fiber seems to inhibit the development of colon cancer by

The force that causes air to move into the lungs during inspiration is supplied by

Treatment with antibiotic drugs, which interfere with the activities of intestinal bacteria, is sometimes followed by a deficiency of

As a group, the B vitamins are

The right lung is composed of which lobes; the left lung is composed of which lobes.

Cholesterol that has been removed from the blood is excreted as a component of bile.