Curious Carrot

Dear Curious Carrot,

For years, some people believed that beta-carotene was a proven cancer fighter. News of its ineffectiveness or even possible harm has recently been spreading. You are not alone in wondering what is happening. Hopefully Alice can sort out the facts.

A few large studies have recently been published stating that beta- carotene is not effective in reducing lung cancer. A widely publicized Finnish study published in the Journal of the American Medical Association followed 29,000 male smokers for 5-8 years. Of those taking beta carotene supplements, 18% more developed lung cancer than those not taking the pills. Another trial, the CARET study looked at 18,000 men and women who smoked heavily or were exposed to asbestos. Although this study was not completed, researchers found 28% more lung cancer in those taking the beta- carotene - Vitamin A combination. In a third study, the Physicians' Health Study at Harvard, 22,000 male physicians were given beta- carotene for 12 years. Their findings showed no benefit or harm of beta-carotene.

In evaluating the findings, we must consider some important points:

1. The first two studies were conducted on smokers and people exposed to asbestos. We do not know if the damage done by these substances was far beyond any possible effects beta-carotene might have had if administered in earlier stages of lung cancer. Also, we cannot apply findings of smokers to non-smokers.

2. Even if we suppose that beta-carotene in the form of supplements is not protective against cancer in well or diseased populations, it is believed that beta-carotene may work in combination with other substances naturally occurring in food.

3. These studies were carried out only on lung cancer. There is evidence that beta-carotene along with other phytochemicals (nutrients of plant origin) may be effective against macular degeneration (an eye disease causing blindness), prostate, and other cancers.

4. Findings from trials done on men cannot be generalized to women. One study currently in progress, the Women's Anti-Oxidant & Cardiovascular Study is following 8,000 women and should provide us with additional insight.

Beta-carotene is a member of a larger family of nutrients termed carotenoids. There are over 500 of these substances. Some examples are lutein and zeaxanthin found in spinach, kale, and broccoli; and lycopenes found in tomatoes and pink grapefruit. It is believed that the interaction of various carotenoids and other nutrients - phytochemicals - help prevent disease. The specific reactions are not all known, but are currently being studied.

Alice hopes that you have already come to the conclusion that taking one pill cannot offer all of the benefits found in fresh fruits and vegetables. To stay healthy, eat a wide variety of these foods, and don't worry about individual supplements!!

Alice

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