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Nutrition is an important part of life, cancer treatment, recovery, and prevention. Food is one of the few things you can be in control of during your treatment. The oncology certified registered dietitians at the Stanford Cancer Center are here to help you make informed choices about nutrition, answer your nutrition-related questions, and help you to achieve and maintain good health.
Phytochemicals (Phytonutrients) as Part of Your Cancer Diet
Phytochemicals can be found in brightly colored fruits, such as berries
Phytochemicals are chemicals found in plants that protect plants against bacteria, viruses, and fungi. Eating large amounts of brightly colored fruits and vegetables (yellow, orange, red, green, white, blue, purple), whole grains/cereals, and beans containing phytochemicals may decrease the risk of developing certain cancers as well as diabetes, hypertension, and heart disease. The action of phytochemicals varies by color and type of the food. They may act as antioxidants or nutrient protectors, or prevent carcinogens (cancer causing agents) from forming.
Sources of phytochemicals
The list below is a partial list of phytochemicals found in foods:
Allicin is found in onions and garlic. Allicin blocks or eliminates certain toxins from bacteria and viruses.
Anthocyanins are found in red and blue fruits (such as raspberries and blueberries) and vegetables. They help to slow the aging process, protect against heart disease and tumors, prevent blood clots, and fight inflammation and allergies.
Biflavonoids are found in citrus fruits.
Carotenoids are found in dark yellow, orange, and deep green fruits and vegetables such as tomatoes, parsley, oranges, pink grapefruit, and spinach.
Flavonoids are found in fruits, vegetables, wine, green tea, onions, apples, kale, and beans.
Indoles are found in broccoli, bok choy, cabbage, kale, Brussel sprouts, and turnips (also known as "cruciferous" vegetables). They contain sulfur and activate agents that destroy cancer-causing chemicals.
Isoflavones are found in soybeans and soybean products.
Lignins are found in flaxseed and whole grain products.
Lutein is found in leafy green vegetables. It may prevent macular degeneration and cataracts as well as reduce the risk of heart disease and breast cancer.
Lycopene is found primarily in tomato products. When cooked, it appears to reduce the risk for cancer and heart attacks.
Phenolics are found in citrus fruits, fruit juices, cereals, legumes, and oilseeds. It is thought to be extremely powerful, and is studied for a variety of health benefits including slowing the aging process, protecting against heart disease and tumors, and fighting inflammation, allergies, and blood clots.
Foods high in phytochemicals
Phytochemicals cannot be found in supplements and are only present in food. Foods high in phytochemicals include the following:
There is no recommended dietary allowance for phytochemicals. Eat a variety of foods, including plenty of fruits and vegetables, to ensure you are getting adequate amounts in your diet.
Broccoli, cabbage, collard greens, kale, cauliflower and Brussels sprouts are all cruciferous vegetables. This vegetable family contains powerful phytochemicals, including carotenoids, indoles and glucosinolates and isothiocyanates, which have been studied and shown to slow the growth of many cancers.