Dear Doctor Column, January 16, 2006

Lifestyle Changes Can Lower Blood Pressure

My blood pressure is 150/90 and one of my New Year’s resolutions is to lower it and avoid medication by changing my diet. Is this a reasonable goal and what’s the best way to accomplish it?

High blood pressure, or hypertension, is a problem for many American adults, who often combine a high-fat, high-sodium diet with stressful schedules that leave little time for exercise. Chronic hypertension damages the body’s organs, putting strain on the heart, brain, eyes, and kidneys, and is a major risk factor for stroke and heart disease, leading causes of death in the United States.

The two numbers in a blood pressure reading indicate pressure inside the blood vessels. The top number indicates pressure when the heart is beating — that’s systolic pressure. Pressure while the heart is at rest between beats is indicated by the bottom number and called diastolic pressure. Optimal blood pressure is a systolic reading of less than 120 mm Hg and a diastolic reading of less than 80 mm Hg.

Lifestyle and dietary changes can lower high blood pressure somewhat and may help you avoid medications or reduce the number of drugs you do need. Following a low-sodium diet can lower blood pressure in people who are sensitive to salt; African Americans, individuals with a family history of hypertension, and those older than 50 years, are most likely to be salt sensitive.

The normal American diet is loaded with salt (sodium chloride) that often hides in processed foods. Canned soups, cheeses, luncheon meats, salad dressings, and many condiments, including ketchup and barbecue sauce, have extremely high sodium levels. For example, a portion of the typical canned cream of mushroom soup has almost 900 mg of sodium, a big chunk of the daily recommended allowance of 2300 mg for healthy people. Individuals with high blood pressure have an even lower recommendation for daily sodium intake – 1500 mg, the amount of sodium in less than ¾ of a teaspoon of salt a day.

Experts suggest that perhaps the easiest and most effective way to cut salt out of your diet is avoiding processed foods and loading up on fruits and vegetables. Eating a diet high in fruits and vegetables — and the latest USDA Dietary Guidelines recommend 9 servings a day — hopefully means you’ll take in fewer calories from other sources. Fresh and frozen fruits and vegetables are naturally low in sodium — canned varieties can have a surprisingly high sodium content, so carefully check nutrition labels — and also are rich in potassium, which plays an important role in heart health and can help lower blood pressure. USDA Dietary Guidelines recommend people get 4700 mg of potassium per day from food, but most American’s diets fall below this standard. Almost all fruits and vegetables are high in this vital mineral, but foods with the highest potassium include avocados, bananas, lima beans, tomatoes, winter squash, and plain low-fat yogurt and other low-fat dairy products.

Other important heart-healthy dietary elements to include in your diet are high-fiber foods (fruits and vegetables again, as well as whole grain breads and pastas and brown rice) and lean sources of protein, such as skinless chicken and fish. The saturated fat found in fatty meats and full-fat milk products can contribute to a rise in blood pressure.

Drinking more than a moderate amount of alcohol — 2 drinks or less per day for men and one drink a day for women — can also increase blood pressure. Other lifestyle changes that can improve your blood pressure are increasing physical activity and reducing body weight. Exercise benefits the heart and can help you lose weight. Even a small amount of weight loss can reduce blood pressure; for every 2 to 4 pounds lost, blood pressure drops by about 1 mm Hg.

Introducing all these changes in your life will definitely have a positive impact on your blood pressure, but you may still need medication to prevent the serious and progressive damage caused by chronic hypertension. Experts estimate that if a person makes comprehensive diet and lifestyle changes, they can reduce their systolic pressure by about 10 to 15 mm Hg, which may not be a big enough reduction for some, depending on their overall risk for heart disease. Talk to your doctor about the changes you plan to make and whether medication is appropriate for you.

People with currently normal blood pressure should also consider these modifications, which can prevent development of high blood pressure. Aging is a risk factor for hypertension, so keeping your blood pressure in the normal range will help stave off serious problems that become more likely later in life. For more information on preventing and treating high blood pressure, go to the National Heart, Lung, and Blood Institute site. To learn more about the most recent USDA Dietary Guidelines read the Dear Doctors column on the recommendations or visit the USDA site.