Brenda Spriggs, MD, MPH, MBA
Cancer is the second leading cause of death in the U.S., according to the National Cancer Institute. Although it causes about a half million deaths annually, more than 60 percent of people diagnosed with cancer survive for five years or more due to improvements in drug therapies, new surgical options and an increased understanding of the role of lifestyle in determining the risk for cancer. The National Cancer Institute suggests that as many as one-third of all cancers may be related to diet. More and more attention has been put on fruits and vegetables to prevent cancer or to improve the outcome for cancer patients. A person considering a dietary change should consult with a doctor first to determine the best regimen.
Broccoli, Cabbage and Cauliflower
Cruciferous vegetables such as broccoli, cabbage and cauliflower contain several chemical compounds that may provide protection against cancer. One of these, called indole-3-carbinol, may deactivate estrogen and reduce the risk of breast cancer. Another compound, a phytonutrient called sulforaphane, may help degrade free radicals and some carcinogenic substances. The U.S. Agriculture Department studied broccoli and found that broccoli sprouts and broccoli that is especially bitter may be highest in sulforaphane.
Carrots are very rich in beta-carotene, a precursor to vitamin A and the compound that gives carrots their orange color. Research on beta-carotene suggests it may reduce the occurrence of many cancers, including lung, stomach, bladder and prostate cancer. Carrots also contain another substance called falcarinol, which slows the growth of cancer cells in the laboratory. However, this compound is destroyed by heat, so it is only available in raw carrots.
According to the Cancer Cure Foundation, some mushrooms such as shiitake, maitake, and reishi mushrooms contain a number of cancer-fighting agents. They contain a polysaccharide called lentinan, which may boost the immune system, and a protein called lectin, which may prevent cancerous cells from dividing. The foundation also indicates that these mushrooms may stimulate production of interferon proteins in the body. In Japan, doctors use mushroom extracts along with chemotherapy for cancer patients.
Black raspberries are very rich in vitamins, minerals and fiber. They also contain several antioxidant compounds known as anthocyanins, which may help decrease the risk of cancer or improve outcomes for cancer patients. In an article published in Cancer Research in 2001, Dr. Laura Kresty reports that feeding black raspberries to rats caused shrinkage of tumors in the esophagus. The Cancer Cure Foundation website indicates that black raspberries may also be effective against colon cancer.
Red grapes are excellent sources of several phytonutrients, including bioflavonoids, which are antioxidants that may help degrade free radicals. They also contain two compounds called resveratrol and ellagic acid. Both of these substances may block enzymes used by cancer cells to grow, potentially slowing the growth of cancerous tumors.