Fruits and Vegetables: More Than What They're Cracked Up To Be!

To reduce the risks of cardiovascular diseases and cancers, high intake of fruits and vegetables has been advised by dietary authorities worldwide. The World Health Organization, for example, recommends eating at least 5 servings of fruits and vegetables daily, excluding potatoes. The scientific community has not yet clarified what factor(s) is responsible for the decreased risk from these deadly diseases. Antioxidants, which are plentiful in fruits and vegetables, have been presumed to exert this preventive effect.

Unfortunately, many people are consuming these antioxidants in supplement form rather than eating fruits and vegetables. This can be shown by the enormous growth that the supplement industry has experienced in the last ten years. According to a recent study, a mere 20 percent of adults in the United States consume this minimum recommended goal of five servings of fruits and vegetables per day. In fact, ten percent of the American population does not consume any fruits or vegetables. Research has also shown that any benefit gained from high antioxidant consumption was due to the intake of a variety of foods abundant in antioxidants. Whether disease prevention can be achieved through supplementation with antioxidants is unclear. Thus, reducing the risks of cardiovascular diseases and cancers may not result solely from antioxidant action.

The major antioxidants consumed from eating whole foods and that are present in commercially available supplement form, include: beta-carotene, vitamin C and vitamin E. Oxygen, which is in the air we breathe, plays two roles in our bodies. It is necessary to sustain life but it also produces substances called prooxidants, which can cause damage to our bodies' cells. Antioxidants, like those mentioned above, defend the cells from the action of prooxidants. Since there is a balance between the formation of prooxidants and their chemical destruction or neutralization by antioxidants, a continuous supply of antioxidants is needed to prevent oxidative damage. Cumulative oxidative damage may be responsible for the initiation of pathological conditions such as cancer and cardiovascular disease.

The belief that food may help promote good health from considerations beyond its nutritional value is beginning to be accepted by the public and the scientific community. Scientists have just recently begun to recognize the importance of a category of chemical substances called phytochemicals.

Evidence is growing, which continues to support the hypothesis that ingestion of foods containing large amounts of phytochemicals may expand the role for diet in the prevention and treatment of disease. Some examples of pertinent phytochemicals include the pigment-containing compounds (e.g., the pigment that make blueberries blue) and flavonoids. Over 4000 different flavonoids have been identified in plants. Many of which have more potent antioxidant properties than those of vitamins C and E.

The protective effects of fruits and vegetables have been theorized to be the result of the combined effects of antioxidants and phytochemicals. Supplement consumption will only provide selected components in a concentrated form, not the various essential phytochemicals that occur in food naturally. Consumers are making an error in judgement by substituting supplements for sound nutritional intake. To a large extent, false advertising that misrepresents the role of dietary supplements in a well-rounded, healthy nutritional diet is misleading consumers. A minimum of 5 servings of fruits and vegetables a day is needed to provide the protective effects given by antioxidants and phytochemicals.

By Scott Mayersohn BS, RD
Registered Dietitian
Newtritiousbeginnings, Inc.

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