Trading in bagels for beans may be a heart-smart move, according to a recent study published in the Journal of the American Medical Association (2005, vol. 294, no. 19). The OmniHeart study, funded by the National Institutes of Health, found that replacing even 10 percent of daily calories from carbohydrates (particularly those found in sweets and desserts) with calories from protein- and monounsaturated fat-rich foods—such as beans, nuts, seeds, and their oils—can help control high blood pressure and reduce the risk of heart disease.

Researchers from Johns Hopkins University and Harvard Medical School compared the effects of three diets on the cardiovascular health of 164 people 30 and older diagnosed with prehypertension or stage 1 hypertension. All three diets were rich in fruits, vegetables, and fiber but had differing amounts of protein, fat, and carbohydrates.

Both the protein-rich diet (which included beans, nuts, and seeds) and the monounsaturated-fat diet (enriched with peanuts and olive and canola oils) lowered blood pressure and "bad" LDL cholesterol, thereby decreasing cardiovascular risk by almost 20 percent. By comparison, the carbohydrate diet reduced risk by 16 percent. "All three diets were beneficial," says Lawrence J. Appel, MD, the study's lead author and professor at Johns Hopkins. "It's just that the two diets [favoring protein mostly from plant sources and monounsaturated fats] were somewhat better." These findings challenge current dietary recommendations from the National Heart, Lung, and Blood Institute that call for higher amounts of carbohydrates to control hypertension.