Antioxidants & Cancer Prevention

Antioxidants are natural compounds, found in foods or supplements, that can protect the body from the damaging effects of free radicals. Antioxidants play a complex role in cancer prevention and include popular vitamins and minerals like selenium, melatonin, and vitamins A, C and E.

Mechanism

• Free radicals are unstable molecules that damage cells--a process that can cause a chain reaction that leads to cancer. Antioxidants neutralize free radicals and prevent cellular damage.

Evidence

• According to the National Cancer Institute, numerous studies have demonstrated a strong link between a high-antioxidant diet and cancer prevention. However, some recent studies regarding vitamin A, a popular antioxidant, have yielded inconclusive results.

Risk

• According to the National Cancer Institute, vitamin A supplements, including beta carotene and retinoid forms of the vitamin, may be associated with an increased risk of lung cancer in smokers. However, this risk is not present in nonsmokers, and researchers are still investigating the underlying causes of this link.

Foods or Supplements?

• Food sources of antioxidants are far superior to supplements as cancer preventatives. A high-fruit, high-vegetable diet is rich in antioxidants and associated with a much lower risk of cancer, and it is not associated with any known risks or medical interactions.

Ongoing Research

• Scientists don't fully understand the relationship between antioxidants and cancer prevention, but government, nonprofit and private organizations are engaged in ongoing research to investigate potential benefits, risks and medical interactions.