Men who eat breakfast cereal at least once a week have a lower risk of heart failure, say researchers in the multicenter Physicians’ Health Study I, which has been tracking the dietary and health habits of more than 20,000 men since 1981. The catch is that the cereal must be at least 25 percent whole grain.

Participants in the study complete a questionnaire once a year about their eating habits. The questionnaire divides cereal consumption into several categories: rarely or never, one to three servings per month, one serving per week, two to four servings per week, five to six servings per week, one serving per day, or two or more servings per day. One serving equals one cup of cereal.

Upon analyzing the data, researchers found that men who consumed seven or more servings of whole-grain cereal per week had a 28-percent lower risk of developing heart failure than men who didn’t eat whole-grain cereal at all. Those who had two to six servings per week had a 22-percent lower risk. Even just one bowl of whole-grain cereal per week appeared to have a benefit: Men in that group had a 14-percent lower risk. There were no heart benefits associated with eating other types of cereal.

Whole-grain cereal may protect the heart in several ways, say the researchers. They note that the potassium in whole-grain cereal may help lower blood pressure, and the cereal’s plant estrogens may help improve blood cholesterol. Also, whole-grain cereal is high in fiber, which helps you feel fuller longer and can help prevent weight gain.

This study was published in the Oct. 22, 2007, issue of the Archives of Internal Medicine.