January 30, 2006

Healthy Diet Combats High Blood Pressure

NEW YORK -- Healthier eating habits could make a big difference in the epidemic of high blood pressure in the U.S., according to a report from the American Heart Association.

Over the past 10 years, studies have bolstered evidence that diets rich in fruits and vegetables and low in sodium can lower a person's blood pressure, the AHA concludes in a scientific statement published in its journal Hypertension.

In addition, one of the benefits of healthier eating -- weight loss -- may also help lower or prevent high blood pressure.

In general, the AHA says, shedding pounds, cutting down on sodium, boosting potassium intake and limiting alcohol are all proven ways to help control blood pressure.

Vegetarian and other diets that emphasize fruits, vegetables, whole grains and low-fat dairy -- including the AHA's Dietary Approaches to Stop Hypertension, the "DASH" diet -- appear effective in bringing these elements together and shaving points off a blood pressure reading.

What's more, the AHA reports, African Americans, who are at particular risk of high blood pressure and its complications, seem to show an especially strong blood pressure improvement when they alter their diets.

According to recent estimates, more than one quarter of U.S. adults have high blood pressure, while another 31 percent are on the verge of the condition. Left uncontrolled, high blood pressure can lead to heart disease, stroke or kidney failure.

"High blood pressure remains an epidemic in the United States, but it can be prevented," Dr. Lawrence Appel, a professor at Johns Hopkins University School of Medicine in Baltimore and the lead author of the AHA report, said in a statement.

"By improving their diet," he said, "people can reduce their blood pressure and put a major dent in their risk of cardiovascular disease, including stroke, coronary heart disease and heart failure."

Of the dietary approaches to lowering blood pressure, Appel and his colleagues note, lowering sodium and increasing potassium intake are among the moves with the best evidence.

Potassium is a chemical element and electrolyte that helps maintain the normal functioning of the heart and nervous system. It is found in foods such as bananas, melons and potatoes, so consuming the recommended eight to 10 servings a day of fruits and vegetables is the best way to get enough potassium, according to the AHA. Cutting down on processed foods is a good way to reduce sodium intake.

More broadly, vegetarian lifestyles and diets that follow the DASH model - limiting saturated fat and red meat, and emphasizing fruits, vegetables and low-fat dairy -- appear to be good overall strategies, according to the AHA.

The evidence is less clear on whether certain other dietary changes -- like getting more calcium or magnesium, or replacing some carbohydrates with protein -- are helpful.

Appel cautioned that adults should not wait until their blood pressure spikes to make lifestyle changes.

"While an individual's blood pressure may be normal now," he said, "90 percent of Americans over 50 years of age have a lifetime risk of high blood pressure. Americans should take action before being diagnosed with high blood pressure."

SOURCE: Hypertension: Journal of the American Heart Association, February 2006.