Well over one million Americans are diagnosed with cancer each year; currently, 10.5 million Americans are fighting or have had cancer in the past. In spite of these alarming numbers, many cancers can be prevented with adequate nutrition and a healthy lifestyle.

It is thought that cancers develop when free radicals produced in biological processes build up in the body and cause damage to cells and their DNA. Eventually, mutations accumulate, allowing cells to evade the mechanisms that control cell growth. Antioxidants neutralize the effects of free radicals by reducing their reactivity. Thus, the risk of many cancers can be decreased simply by taking antioxidants, which include vitamins A, C and E, and the vitamin A precursor beta carotene. The minerals selenium and zinc also play a large role in activating natural antioxidant enzymes in our cells. Antioxidants can be supplied by everyday foods; both fruits and vegetables contain good amounts of antioxidants. Some researchers speculate that folic acid keeps DNA healthy and prevents mutations that can lead to cancer.

Vitamin D, though not an antioxidant, is another important vitamin that can defend the body against cancer. Its anti-tumor activity, when coupled with calcium supplements, reduces the risk of colon and rectal cancers.

Foods in our everyday diet also have beneficial effects. Eating garlic on a regular basis serves as a good protection against esophageal, stomach, and colon cancer. Regular consumption of fish can decrease the risk of the blood cancers leukemia, myeloma, and non-Hodgkin's lymphoma, as well as endometrial cancer in women. The active compound in fish oil is the omega-3 fatty acid. Preliminary evidence suggests that omega-3 fatty acids are first oxidized and then accumulate in tumor cell membranes, resulting in cell membrane perforation and eventually tumor cell death. Fish oils might decrease production of lactic acid by tumor cells. Lactic acidosis is a marker of unfavorable metabolic conditions associated with many cancers. And green tea has been shown to wield anticancer properties. In fact, some scientists believe that a chemical in green tea called EGCG may be one of the most powerful anticancer compounds ever discovered.