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What is the DASH diet?

Dietary Approaches to Stop Hypertension, known as DASH, is a study supported by the National Heart, Lung, and Blood Institute.

What the Study Did

In this study, 459 adults ate one of three diets:

  • a typical American diet
  • a typical American diet with an increase in fruits and vegetables
  • the DASH diet, which is a diet rich in fruits and vegetables and lower in saturated fat, total fat, and cholesterol

All three diets included about 3,000 mg of sodium daily. This is less than the amount a typical American consumes.

The DASH diet includes as many as 10 servings of fruits and vegetables and up to 3 servings of low-fat dairy products. And that means that it also contains about two to three times more potassium, magnesium, and calcium than the average American diet. These nutrients may be important in preventing high blood pressure.

What the Study Found

Researchers found that the DASH diet lowered blood pressure more than the other two diets. Here are the specific results.

  • For people without high blood pressure, the DASH eating plan reduced systolic blood pressure - the top number - an average of 6 points. It reduced diastolic blood pressure - the bottom number - an average of 3 points.
  • For people with high blood pressure, the results were even better. The DASH diet reduced systolic pressure an average of 11 points. And it reduced diastolic pressure an average of 6 points.

The blood pressure reductions occurred within 2 weeks of starting the eating plan. Results of a study published in December 2001 in The Annals of Internal Medicine showed that you can reduce your blood pressure more by eating less sodium eating less sodium and following the DASH diet than you can by taking either of these steps alone.