Apple a day: Key to keeping cardiologist away?

ripe red apple with green leaf isolated on white

(CBS) Everyone. That's who stands to benefit from eating apples, if you believe the author of a new study that shows heeding the familiar "apple a day" adage can bring significant declines in key risk factors for heart disease.

In addition to a sharp drop in levels of LDL (bad) cholesterol, participants in the study saw declines in lipid hydroperoxide and C-reactive protein. There were also slight increases in levels of heart-protecting HDL (good) cholesterol.

"I never expected apple consumption to reduce bad cholesterol to this extent while increasing HDL cholesterol or good cholesterol by about 4 percent," researcher Dr. Bahram H. Arjmandi, chairman of the department of nutrition, food and exercise sciences at Florida State University, said in a written statement.

In the study, 160 women between the ages of 45 and 65 were randomly divided into two groups. Every day for a year, women in one group got dried apples, women in the other group prunes. Blood tests administered at three, six, and 12 months charted the changes in the women's cardiovascular risk.

The study was scheduled to be presented at the Experimental Biology 2011 conference held April 9-13 in Washington, D.C.

As for what might explain the apples' beneficial effects, researchers singled out two compounds found in the fruit: a carbohydrate known as pectin and a class of antioxidants known as polyphenols. The heart-protecting effects of these substances have been shown by previous studies involving animals, according to the statement.

Apples are low in calories and contain lots of vitamin C and vitamin A, according to the U.S. Department of Agriculture Food and Nutrition Service website. They also contain boron, a bone-building mineral.

Did eating all those apples cause the women to gain weight? No. Dr. Arjmandi said women in the apple group lost an average of 3.3 pounds, adding that the pectin might have been responsible for the weight loss. Pectin increases satiety by slowing the emptying of food from the stomach, according to recent research.

The abstract of the study study doesn't explain what happened with the women in the prune group, and neither Dr. Arjmandi nor the nutrition advisor for the California Dried Plums organization returned phone calls from CBS News by press time.

An apple a day keeps the doctor away: where'd that come from anyway? According to the Phrase Finder website, it's one of several variants of the proverb "Eat an apple on going to bed, and you'll keep the doctor from earning his bread," which first appeared in print in 1866.