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

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.”

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.