Prevent Cancer & Heart Disease with Phytochemicals

Wednesday, October 25, 2006 - 10:34am

By Dena McDowell, MS, RD

Perhaps you have heard of the term phytochemical. However, you may not know what it means or why you need it. Simply put, phytochemicals are naturally present substances found in fruits and vegetables. While these non-nutritive plant chemicals are not essential for our bodies, consumption is very important as they can help ward off certain types of cancers and lower the risk of heart disease.

Food: The Best Source of Phytochemicals

There are more than 1000 phytochemicals found in food sources. These chemicals act as antioxidants, phytoestrogens, enzyme aids, and serve as antibacterial functions. According to both the American Heart Association and the National Cancer Institute (NCI), it is important to eat whole foods to get the maximum benefit of phytochemicals. Scientists know that phytochemicals work with the vitamins, minerals, and fiber in foods to synergistically protect against aging, heart disease, and cancer. Taking a supplement is not recommended to get these powerful chemicals into your body.

Eat 5 to 9 Servings of Fruits and Vegetables Everyday

A recommended daily amount of phytochemicals has not been established. However, the NCI recommends striving for at least 5 to 9 servings of fruits or vegetables a day to get adequate amounts of these important chemicals as well as other vitamins, minerals, and fiber.

Serving sizes for fruits and vegetables include:

  • 1 cup of 100% natural fruit or vegetable juice
  • 1 cup of cut up fruit or vegetables
  • 2 cups of leafy greens
  • 1/2 cup of dried fruit.

Whenever possible, choose darker colored fruits and vegetables to maximize the phytochemical content. Follow the chart below to eat according to the rainbow:

Phytochemicals and the Rainbow of Color




Health Benefits


Strawberries, raspberries, red apples, blood oranges, cherries, red pears, pomegranates, watermelon, red pepper, radishes, red potatoes, rhubarb, tomatoes

Anthocyanidins, flavonols, flavones, proanthocyanidins,

Ellagic acid, resveratrol

Protects against heart disease and certain cancers. Aids in memory and urinary tract function.

Yellow & Orange

Yellow apples, citrus fruits, peaches, apricots, carrots, sweet potatoes, butternut squash, summer and winter squash, yellow pears, pumpkin, yellow tomatoes, cantaloupe, lemon, mangoes, papaya, pineapple, tangerines

Flavonols, Flavonones, Alpha-Carotene,



Protects against heart disease and certain cancers. Boosts immune system.


Lettuce, kiwis, broccoli, green pears, green grapes, green beans, avocados, honeydew, limes, green peppers, sugar snap peas, peas, spinach, cucumbers, zucchini, Brussel sprouts, artichokes, leeks, green onions

Flavones, flavonanones, flavonols,

Beta-carotene, lutein, zeaxathin, indoles, isothiocyanates, organosulfur compounds

Reduces risk of certain cancers. Improves vision and helps build bones and teeth.

Blue & Purple

Plums, blueberries, blackberries, black currants, purple grapes, eggplant, raisins, purple cabbage

Flavonols, anthocyanidins, proanthocyanidins,

Ellagic acid, resveratrol

Reduces risk of certain cancers. Protects urinary tract from infection. Helps memory and reduces free radical damage during aging process.


Cauliflower, onions, garlic, kohlrabi, bananas, brown pears, white peaches, white nectarines, mushrooms, potatoes, shallots, white corn, soy products

Flavonols, flavonanones, indoles, isocyanates, organosulfur compounds

Protects against heart disease and certain types of cancer. May reduce cholesterol levels. Soy produces estrogenic effect; helpful to reduce hot flashes during menopause.

For further information on the correlation between food and color see the following articles on TheDietChannel: Eat A Rainbow, Part 1, Part 2, Part 3 and Part 4.