A diet that includes the regular consumption of a variety of fruits and vegetables is felt to lower the risk of developing certain cancers. And, unlike some foods, their consumption, in any amount, has not been linked to an increase in any kind of malignancy. The cancer-preventing properties of fruits and vegetables likely result from their antioxidant content. Antioxidants de-activate free radicals and assist in detoxification, both of which helps to eliminate carcinogens from the body. It is estimated that the majority of Americans fail to meet the recommended daily intake of fruits and vegetables.
The amount of antioxidant activity varies greatly according to the growing seasons and the soil in which the fruits and vegetables are grown. Plants under stress produce more antioxidants as a response to the stress. Different fruits and vegetables will vary in their antioxidant activity. Some of the more potent antioxidants are found in strawberries, grapefruit, garlic and kale.
Fruits and vegetables also assist the body in the process of detoxification. Detoxification is a process whereby the body eliminates toxins, metabolic waste products, and other non-useable substances. Cruciferous vegetables and carotenoids are helpful in this area.
Fruits and vegetables also contain fiber. The type of fiber that contributes to the lowering of cancer risk is the insoluble kind. It does this by contributing to a slower rise in blood sugar, preventing the hyperinsulinemia associated with an increased risk of cancer. It also adds bulk to the stool, allowing for better elimination of toxins and products of detoxification. The average American diet is high-fat and low-fiber and would benefit from the addition of more fiber from fruits and vegetables.
The World Cancer Research Fund states there is convincing evidence that fruits and vegetables decrease the risk of developing cancers of the mouth, pharynx, esophagus, lung, stomach, larynx, pancreas, breast, and bladder, and possibly cancers of the cervix, ovary, endometrium, and thyroid.