NEW YORK (Reuters Health) - Research shows that boosting levels of potassium in the diet may lower a person’s risk of developing high blood pressure and may decrease blood pressure in people who already have “hypertension.”

Bananas are readied for sale at a Wal-Mart store in Santa Clarita, California April 1, 2008. REUTERS/Mario Anzuoni

High blood pressure remains the chief reason for visits to doctors’ offices and for prescription drug use in the U.S., two researchers from Nashville, Tennessee note in a special supplement to The Journal of Clinical Hypertension this month.

Dr. Mark C. Houston, from Vanderbilt University School of Medicine and Dr. Karen J. Harper from Harper Medical Communications, Inc. in Nashville, also point out that a healthy intake of potassium is thought to be one reason why vegetarians and isolated populations have a very low incidence of heart disease.

In isolated societies consuming diets low in sodium and high in fruits and vegetables, which have and therefore high levels of potassium, hypertension affects only 1 percent of the population, they note. In contrast, in industrialized societies, where people consume diets high in processed foods and large amounts of dietary sodium 1 in 3 persons have hypertension.

The typical American diet contains about double the sodium and half the potassium that is currently recommended in dietary guidelines. Low potassium intake is thought to contribute to the prevalence of high blood pressure in Americans.

Based on their review of published studies on the topic, Houston and Harper say if Americans were to boost their potassium intake, the number of adults with known high blood pressure could fall by more than 10 percent. In 2006, the American Heart Association issued new guidelines calling for Americans to get 4.7 grams per day of potassium.

“An increase in potassium with a decrease in sodium is probably the most important dietary choice (after weight loss) that should be implemented to reduce cardiovascular disease,” Houston and Harper contend.

Some studies also show that diets containing at least 500 to 1,000 milligrams magnesium daily and more than 800 milligrams of calcium daily may help lower blood pressure and the risk of developing high blood pressure.

“A high intake of these minerals through increased consumption of fruits and vegetables may improve blood pressure levels and reduce coronary heart disease and stroke,” Houston and Harper conclude.

SOURCE: Journal of Clinical Hypertension, July 2008.