Q: I have followed a low-salt diet and taken several medications, but my blood pressure is still too high. Can I make any other changes in my diet that will help to lower my blood pressure?
A: Experts generally believe that for overweight people weight loss is the most effective dietary or lifestyle measure to lower blood pressure. Of course, weight loss can be achieved by decreased caloric intake, increased physical activity or preferably a combination of the two. And maintenance of ideal body weight has many health benefits in addition to its impact on blood pressure.
Second in importance to weight control is restriction of the amount of sodium in the diet. The benefits of sodium restriction are greatest in those who start with the highest blood pressure and make the largest change in their sodium intake. Most people in this country can cut their sodium intake in half by not adding salt during cooking or at the table and by avoiding processed foods with a high sodium content. Because Americans generally eat far more sodium than they need, there are no risks to reducing the amount of dietary salt.
Next in importance as a lifestyle measure for controlling blood pressure is reducing alcohol use.
Finally, a recent study in the Annals of Internal Medicine showed impressive reductions in blood pressure when subjects on a yearlong, high potassium diet were compared with those on a normal diet. Nonetheless, a diet containing many potassium-rich foods is still considered less effective in lowering blood pressure than the measures cited above. Foods high in potassium include legumes, many vegetables and fresh fruit. A raised intake of these foods can also lower dietary fat, a commonly recommended measure for the prevention of heart disease. Only people with severe kidney disease are in any danger from a high potassium diet.
Dr. Margolis is professor of medicine and biological chemistry at the Johns Hopkins School of Medicine and associate dean for faculty affairs at the school.