All the way through history people have survived well when the diet were comprised of fruits and vegetables. Science has now proven without any doubt that there is a connection between the fruits and vegetables and your health.
There is evidence of a correlation between consuming fruits and vegetables and reducing gastric and colon cancer. All fruits and vegetables contain fiber which is useful in preventing colon cancer. The dietary fiber is also fermented by bacteria in the colon that lead to short chained fatty acids which guard against cancer causing substances. Tomatoes may shield against esophageal cancer and prostate cancer and carrots against cancer in the mouth.
The reason fruits and vegetables are protective against cancer is because they contain antioxidants, raise activity of enzymes that detoxify cancer causing substances, altering estrogen metabolism and altering the bacteria and pH in the colon.
For example, garlic, onions, scallions and allium vegetables are rich in sulfur compounds which augment enzymes to inhibit bacteria that convert nitrates to nitrites in the stomach, and nitrites can combine with amines to form nitrosamines which can cause cancer of the stomach. Cruciferous vegetables such as cauliflower, broccoli and cabbage have a high content of organic sulfur which can stimulate enzymes in the gut to detoxify cancer causing substances.
These vegetables also contain indole-3-carbinol which affects estrogen metabolism and shield against endometrial and breast cancer. Green vegetables such as spinach, lettuce and mustard greens have high levels of antioxidants which block damage from free radicals within a cell. Green leafy vegetables also contain high levels of folic acid which can defend against colon cancer.
Fruits and vegetables, like red peppers, tomatoes and raspberries, are rich in lycopene which act as antioxidants and have revealed to protect against prostate cancer. Citrus fruits are rich in vitamin C – again acting as antioxidants and also preventing the formation of nitrosamines. Yellow fruits and vegetables are rich in beta carotene which is also an antioxidant and can be metabolized to vitamin A which facilitates to maintain healthy cells.