Phytonutrients are the new hot item in diet and nutrition. But what are they and why are they believed to be so healthful?
Phytochemicals are a class of compounds found in the highly colored skins of some fruits and vegetables. Since their nutritional properties are still under investigation no FDA guidelines are available about their health benefits. As a result, some avoid labeling them phytonutrients.
Still, numerous studies suggest that these compounds are very likely to have beneficial effects. Further, no one doubts that the foods that contain them are good nutrition. They are recommended by all experts. The chief area needing clarification is the degree to which they aid in combating certain diseases, such as colon cancer, or how effectively they aid the immune system.
What Foods Contain Phytonutrients, and How Do They Help?
Any strongly colored fruit or vegetable will contain some phytochemicals.
Tomatoes are rich in lycopene. While research is ongoing, many large scale studies have already shown a link between consumption and reduction of prostate cancer. In one, men who consumed more than 10 servings per week had a 35% lower risk, compared to those who only consumed 1.5 servings or fewer.
'Eat your spinach' is a familiar phrase from childhood. Phytochemicals called carotenoids may be the reason that it is good advice. Those who consumed it regularly had a 46% lower risk of macular degeneration, compared to study participants who only ate it once per month or less.
Another category called flavonoids are well-known to be beneficial, based on thousands of studies. That's because they act as antioxidants. Roaming oxygen atoms called free radicals carry enough energy to damage cells. Antioxidants combine with them and render them harmless. Flavonoids are a rich source of antioxidants.
According to a European study published in Lancet, a leading British medical journal, Dutch men who consumed more than 30 mg of flavonoids daily had a 58% lower risk of heart disease than those who consumed only 19 mg or less per day.
Flavonoids are part of a larger class called polyphenols that have similar properties. They are in such foods as strawberries, blueberries, apples and more. Red wine, long known to be a boon to health in moderate quantities, contains polyphenols.
A study in the Journal of the AMA (American Medical Association) linked fruit and vegetable consumption to a decrease in the odds of stroke. For each additional consumption of three daily servings subjects had a 22% decrease in the chances for hemorrhagic and ischemic stroke.
How Much Do We Get?
The average American gets 3.3 servings of vegetables per day. But those containing phytochemicals are consumed in much smaller quantities, only about 0.2 servings. About 10% of the population eats less than one serving per day of vegetables.
Less than a third of the population (29%) eats the minimum number of daily fruit servings. Nearly half eat less than one serving of fruit per day. Even for those on a restricted carb diet that is very low.
Summary
Like many areas of nutritional science, research on phytochemicals continues at a rapid pace. But even at the present level of knowledge it's clear that certain fruits and vegetables should be part of a healthy, balanced diet.
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