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The benefits of vitamin pills and chocolate

Ask the doctor

vitamin pills and chocolate
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Q. Do vitamin pills reduce a person’s risk of heart disease and cancer, or not? I hear different things. And recently, I hear people saying chocolate is heart-healthy. Is that too good to be true?

A. I’m a committed chocoholic. Once I was in an ice cream store and saw a flavor called “Triple Chocolate Death,” and I said to myself: “What a way to go!” Recently, a colleague told me about a flavor called “Chocolate Therapy,” which shows how attitudes are changing.

Regarding vitamins, many studies find that people who eat vitamin-rich foods have lower levels of heart disease and cancer. For vitamin pills, however, the evidence is much less clear. There’s reason to think that multivitamin pills containing relatively high doses of B vitamins, or B vitamin pills alone, might reduce your risk of heart disease. Harvard’s large Nurses’ Health Study found that people who eat a lot of foods rich in folic acid have lower blood pressure, which reduces the risk of heart disease. Folic acid (a B vitamin) and vitamin B12 pills also lower blood levels of a natural molecule called homocysteine. Very high blood levels of homocysteine are associated with heart disease. Yet, B vitamin pills don’t lower the risk of heart disease in people with normal or somewhat high homocysteine levels. And no large studies have tested whether B vitamins are valuable in those unusual people with very high levels.

Folic acid also plays an important role when our cells make DNA. Damaged DNA can lead to cancer. So there’s a rea-son to think B vitamin pills might lower the risk of cancer. However, randomized trials of folic acid have come to different conclusions, so the jury still is out.

As for chocolate, there’s reason to think it might be beneficial. Cocoa beans (from which chocolate is made) contain flavanols, chemicals found in plants. Flavanols lower blood pressure and make blood less likely to clot. They also are antioxidants, which probably reduces the formation of artery-clogging plaques. All of these effects could lower the risk of heart disease. However, chocolate candies also contain fats, including “bad” saturated fats that are not good for the heart.

So, although theoretically multivitamins and chocolate might reduce the risk of heart disease and some cancers, proof from randomized trials is lacking. Fortunately, a new randomized trial called COSMOS, led by colleagues based here at Harvard, will test whether multivitamin pills and cocoa pills have health benefits. COSMOS will enroll men ages 60 or older and women ages 65 and older who have not previously had a heart attack, a stroke, or cancer (other than skin cancer). For information as to how you might be able to participate in this study, call 800-633-6913, or email the COSMOS team at

— Anthony Komaroff, MD
Editor in Chief, Harvard Health Letter

Posted by: Dr.Health

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