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How Phytochemicals Work

Are There Any Dangers to Phytochemicals?

­Alt­hough there isn't a lot of research to date on phytochemicals, experts say that they are generally healthy and safe when eaten as part of a balanced diet containing a wide range of fruits and vegetables. What raises concern is when they are ingredients in nutritional supplements, which are not regulated by the Food and Drug Administration.

Supplements cannot begin to replicate the wide variety of phytochemicals that occur naturally in foods; and in high concentrations, they might actually be dangerous. Certain phytochemicals in supplements have in fact been found to contribute to cancer cell growth. Beta-carotene, although it can be beneficial when taken naturally, has been found to increase the risk of lung cancer in male smokers when taken in a high-dose supplement. Some flavonoids can cause serious gastrointestinal or allergic problems when taken in high doses.

How Much Should You Eat?
The government's new dietary guidelines suggest that adults who are on a 2,000-calorie-a-day diet eat at least two cups of fruit and two and a half cups of vegetables every day. Experts say the deeper the color of the fruit or vegetable, the more protective phytonutrients it contains. And don't forget the whole grains -- they also contain a range of phytonutrients.


For more information on phytochemicals and related topics, check out the links on the next page.