The level of evidence for permitting a qualified health claim: FDA's review of the evidence for selenium and cancer and vitamin E and heart disease.

Health claims are authorized for the labeling of foods when there is significant scientific agreement among qualified experts on the evidence for a relationship between a food or food component (substance) and a disease. Qualified health claims are permitted when there is less scientific evidence for a substance-disease relationship, therefore requiring qualifying language. The evidence for a relationship between vitamin E and heart disease and selenium and cancer was reviewed by the U.S. FDA. It was determined that there was insufficient evidence to permit a qualified health claim for vitamin E and cancer, whereas there was some evidence for permitting a qualified health claim for selenium and cancer. The rationale for these conclusions is discussed below.