Weight loss, less salt avert hypertension.

Eating less salt and losing weight can stave off high blood pressure, according to a study of people at high risk of developing this condition, known as hypertension.

"Most people are going to develop hypertension at some point," says study leader Paul Whelton of Johns Hopkins Medical Institutions in Baltimore. "We need to show people how they can prevent it."

Nearly two-thirds of the U.S. population will eventually suffer high blood pressure, but doctors can control the condition in only 21 percent of patients. Preventing hypertension could cut the 1.5 million heart attacks and 500,000 strokes in the United States each year.

The researchers studied 2,382 overweight men and women with "high normal" blood pressure-above the average 120 millimeters of mercury (mm Hg) over 80 mm Hg, yet below the high blood pressure cutoff of 140 over 90. Blood pressure is recorded as systolic pressure, during contractions of the heart, over diastolic pressure, between heartbeats. Nearly 80 million people in the United States register in the high normal range

Volunteers not assigned to a control group were counseled to lose weight, cut salt from their diet, or do both. After 6 months, people in the three study groups had, on average, lost 10 pounds, reduced sodium intake 25 percent, and seen a drop of 4 mm Hg in systolic pressure and 3 mm Hg in diastolic pressure. Whelton estimates that every 2 mm Hg decrease in diastolic pressure decreases heart attacks by 6 percent and strokes by 15 percent.

As he reported at the American Heart Association annual meeting in Anaheim, Calif., last week, maintaining those health gains wasn't easy. After 36 months, participants averaged only a 1 mm Hg drop in systolic blood pressure, with no decrease in diastolic blood pressure, and had regained 5 to 6 pounds. Nonetheless, 20 percent fewer people developed hypertension in the study groups than in the control group.

Whelton notes that 80 percent of the sodium in U.S. diets comes from prepared foods and argues that health professionals "have to work with manufacturers to lower sodium."

Jeffrey Cutler of the National Heart, Lung, and Blood Institute in Bethesda, Md., says the institute is encouraging the food industry to reduce sodium and calories. Cutler maintains that "the potential is there to prevent probably the majority of the cases of hypertension with these 'simple' lifestyle changes."