A diet high in fiber and low in fat may reduce the risk of colon and rectal cancers. Fiber provides bulk in the diet, and it helps move food through the intestines and out of the body at regular intervals. It is unclear whether it is total fiber intake or the components of dietary fiber that is beneficial in reducing cancer risks. Evidence suggests that certain compounds in plant food sources, particularly fruits and vegetables, can be cancer fighting. These compounds are called phytochemicals, which is actually a general name for several cancer-fighting substances, such as flavonoids, allylic sulfides and sulforaphanes.
Scientists believe that the compounds stop cancer cells from initiating or developing into tumors.
While there is no direct proof these compounds can prevent cancer, eating a diet with plenty of fruits and vegetables has proven to be a healthy food choice. Obtaining anticancer substances from food rather than supplements may be the best plan of action to prevent disease. Our bodies convert beta carotene to vitamin A. Epidemiological studies suggest that eating foods that contain beta carotene decreases the risk of a variety of cancers. Supplements are not found to provide the same benefit, and excess vitamin A can be toxic. Deep yellow-orange fruits, such as apricots, peaches and cantaloupe, also are good sources.