Applying science to changing dietary patterns

Abstract

The intake of 400-600 g/d of fruits and vegetables is associated with reduced incidence of many common forms of cancer. These foods contain phytochemicals that can modulate gene expression to inhibit carcinogenesis via multiple pathways. Many phytochemicals are colorful, providing an easy way to communicate increased diversity of fruits and vegetables to the public. Red foods contain lycopene, the pigment in tomatoes, which is localized in the prostate gland and may be involved in maintaining prostate health. Yellow-green vegetables, such as corn and leafy greens, contain lutein and zeaxanthin, which are localized in the retina where age-related macular degeneration occurs. Red-purple foods contain anthocyanins, which are powerful antioxidants found in red apples, grapes, berries and wine. Orange foods, including carrots, mangos, apricots, pumpkin and winter squash, contain β-carotene. Orange-yellow foods, including oranges, tangerines and lemons contain citrus flavonoids. Green foods, including broccoli, Brussels sprouts and kale, contain glucosinolates. White-green foods in the onion family contain allyl sulfides. Consumers are advised to ingest one serving of each of the above groups daily, putting this recommendation within the National Cancer Institute and American Institute for Cancer Research guidelines of five to nine servings per day. The color code provides simplification, but it is also important as a way to help consumers to find common fruits and vegetables easily while traveling, eating in restaurants or working. At home, simple ways of preparing foods rapidly and easily are needed to influence dietary patterns.