The potency of antioxidants is only just becoming appreciated
Imagine what life would be like without color. Sports cars wouldn't be red, denim wouldn't be blue, and spinach wouldn't be green. And if the chemicals that make most vegetables green weren't around, you'd be likely to find yourself a lot more susceptible to several serious diseases, including heart disease and a common form of blindness.
The chemicals are called carotenoids, and like vitamins, they belong to a category of compounds known as antioxidants. Antioxidants have been widely credited with having amazing effects when it comes to fighting off chronic disease and aging. They are said to squelch the body's production of free radicals, which are oxygen molecules missing an electron.
Scientists have long suspected that chronic diseases like heart disease and cancer may be triggered when free radicals try to replace "AWOL" electrons by stealing from neighboring molecules, resulting in cell breakdown and the onset of disease.
A 1994 study in the New England Journal of Medicine unexpectedly questioned these assumptions, however. When supplied as dietary supplements, neither beta- carotene, which is the best-known of the carotenoids, nor Vitamin E appeared to protect heavy smokers from lung cancer. The results of the study even suggested that beta-carotene might contribute to higher rates of lung cancer in heavy smokers.
But a more recent study by researchers at the University of North Carolina and University of Tennessee and published in the Journal of the American Medical Association has provided new evidence that carotenoids do cut the risk of heart disease.
Unlike the earlier Harvard study, which measured only the effects of beta-carotene and Vitamin E taken as supplements in pill form, the North Carolina-Tennessee study measured the presence of all carotenoids in the bloodstream and found that among nonsmokers, those with the highest carotenoid levels were 70 percent less likely to suffer a heart attack than those with the lowest carotenoid levels. Among those who smoke, the benefits were less dramatic but still significant.
A third recent Harvard study found that consuming vegetables rich in carotenoids seemed to lower substantially the risk of developing a form of blindness common among the elderly.
Scientists remain uncertain which carotenoids or antioxidants in vegetables may supply the protective effects. They do know enough, however, to urge that your diet should include hearty daily servings of vegetables and fruits.
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