What Is the DASH Diet?

By Malia Frey  
Reviewed by Amanda Baker Lemein, MS, RD 
Updated on December 10, 2020

Are you trying to lower your blood pressure with dietary changes? If so, you're not alone. High blood pressure affects 108 million people in the United States. That’s nearly half of all American adults, or 45%.1 And the condition, also known as hypertension, can have serious complications.

The DASH Diet is the eating program most frequently recommended for reducing blood pressure. But this widely studied diet plan can provide other benefits as well. Learn how this eating style compares to other diets and, with the guidance of a registered dietitian or health care provider, consider the pros and cons to decide if it might be a smart program for you.

What Experts Say

The DASH diet is an eating plan developed to reduce blood pressure. The recommended foods and variety offer results supported by research. However, if they are packaged as a weight loss plan, negative consequences of dieting may apply.

—Willow Jarosh, MS, RD

Background

In 1992, researchers from the National Institutes of Health received funding to investigate if dietary changes could reduce blood pressure in test subjects. They began a trial named Dietary Approaches to Stop Hypertension (DASH). There were 459 adults enrolled in the study, some with high blood pressure and some without.

For three weeks, test subjects were fed a control diet that was low in fruits, vegetables, and dairy products, with a fat content typical of the average diet in the United States at the time. After that initial phase of the research, subjects were randomly assigned to one of two groups. One group ate a diet rich in fruits and vegetables. The other group ate a “combination” diet rich in fruits, vegetables, and low-fat dairy products and with reduced saturated and total fat. Sodium intake and body weight were maintained at constant levels.

Study authors found that a diet rich in fruits, vegetables, and low-fat dairy foods and with reduced saturated and total fat can substantially lower blood pressure. Their findings were published in the New England Journal of Medicine in 1997.2

Specifically, researchers found that the combination diet reduced systolic and diastolic blood pressure by 11.4 and 5.5 mm Hg more than the control diet in people with hypertension. In people with normal blood pressure, the diet was also able to reduce blood pressure, although less significantly.

The diet was further studied in trials including the Optimal Macronutrient Intake Trial for Heart Health (OmniHeart). Additionally, researchers began to study different sodium levels combined with the DASH Diet to see if it would result in further benefits for those with high blood pressure.

In 2001, researchers published another study in The New England Journal of Medicine finding that lower sodium levels combined with the DASH Diet can substantially lower blood pressure. They also suggested that "long-term health benefits will depend on the ability of people to make long-lasting dietary changes and the increased availability of lower-sodium foods."3

Since that time, the DASH Diet has become one of the most widely studied, widely recommended, and widely recognized diets. Free resources are available to consumers on the National Institutes of Health website, making it one of the most easily accessible diets.

How It Works

The DASH Diet is not a diet that you follow for a short period of time to lose weight. Instead, it is an eating style that is followed for life to support overall health and wellness. There are no specific calorie requirements and no foods that are off-limits.

Following the diet means building meals around foods from a variety of different food groups and trying to limit sodium to 2,300 milligrams or 1,500 milligrams per day, depending on dietary needs. You can also expect to reduce intake of foods that are high in saturated fats, like fatty meats, full-fat dairy products, and tropical oils such as coconut, palm kernel, and palm oils.

You are advised to eat plenty of fruits and vegetables, whole grains, fish, poultry, legumes, and low- or non-fat dairy products, along with limiting sugar-sweetened beverages and foods.

To figure out how many servings of each food group to consume, you first determine your total calorie intake level. Calorie level recommendations vary based on age, gender, and activity level.

Women can expect to consume 1,600 to 2,400 calories per day. Men can expect to consume 2,000 to 3,100 calories per day. You are not required to count calories. But the more calories you can consume per day, the more servings you'll consume from each food group.