DASH diet and exercise helps uncontrolled high blood pressure, study finds

While practicing taking vital signs, classmates work on taking each others blood pressure in an EMT class on Monday, Feb. 22, 2021, at SCC's Health Sciences building in Lincoln, Neb. (Gwyneth Roberts/Lincoln Journal Star via AP)

Nearly half of all Americans live with high blood pressure, a key contributor to diabetes, heart disease, kidney disease, stroke and serious complications from COVID-19, according to the American Heart Association.

Popping a pill or two to control that hypertension is common, but is that enough? The answer is likely no for more than one-third of the adults in the United States currently taking blood pressure medications, according to a new study analyzing federal data on 13,000 adults.

Younger men from ages 20 to 49 were up to 70% more likely to have uncontrolled hypertension than women of the same age, the study found. However, risk shifted when women reached the age of 70, when women were 29% to 63% more likely to have uncontrolled hypertension than men, according to the study presented Monday at an AHA conference on hypertension.

Also called "resistant" hypertension, a person's blood pressure is considered uncontrolled when they still have high readings despite the concurrent use of three types of medications. The study defined high blood pressure using the AHA guidelines as anything above 130 systolic (top number) and over 80 diastolic (lower number).

"Blood pressure control remains a major public health challenge that impacts even those being treated for the disease," said study author Dr. Aayush Visaria, a postdoctoral research fellow at Rutgers University in New Brunswick, New Jersey, in a statement.

Young men between the ages of 20 and 29 were 59% more likely to have uncontrolled hypertension than women of that age. Men between the ages of 30 and 39 were 70% more likely, and men ages 40 to 49 were 47% more likely to be uncontrolled.

"These results indicate that women 70 years and older and men less than 50 years with hypertension may have increased risk of uncontrolled hypertension and may benefit from more frequent blood pressure monitoring," Visaria said.

What to do?

But there is something people with stubbornly high blood pressure can do -- and it's more than just pop another pill.

In what authors are calling the first study of its kind, people were able to reduce resistant high blood pressure with a combination of diet, exercise and reducing salt intake. The study published Monday in the AHA's journal Circulation.

"Though we usually think about recommending lifestyle changes like losing weight and getting more physical activity before starting medications, this study provides important reinforcement that adding lifestyle changes in conjunction with medications -- and when medications alone are not doing the job -- is an effective strategy," said Bethany Barone Gibbs, an associate professor in the department of health and human development at the University of Pittsburgh, in a statement. Gibbs was not involved in the study.

DASH diet and exercise works

Over a four-month period, 90 adults with uncontrolled high blood pressure were given weekly dietary advice on how to follow the DASH diet, which stands for Dietary Approaches to Stop Hypertension.

An award-winning eating plan, DASH has a simple premise: Eat more veggies, fruits and low-fat dairy foods; limit foods high in saturated fat; and limit your intake of sodium to 2,300 milligrams a day -- that's about 1 teaspoon of table salt.

The DASH meal plan includes four to six servings of vegetables and another four to six servings of fruit; three servings of whole-grain products; two to four servings of fat-free or low-fat dairy dairy products; and several servings each of lean meats and nuts, seeds and legumes each day.

In addition to the coaching and meal plan, the 90 people in the study engaged in intensive, supervised exercise training at a cardiac rehabilitation facility three times a week.

Another 50 people with resistant hypertension sat in on a single session with a health educator and went home with written guidelines on exercise, weight loss and nutritional goals to follow on their own.

The results? People in the guided group reduced their systolic blood pressure by at least 12 points, compared to a reduction of 7 points in the group who had no structured help.

"While some people can make lifestyle changes on their own, a structured program of supervised exercise and dietary modifications conducted by a multidisciplinary team of health care professionals in cardiac rehabilitation programs is likely more effective," said senior study author James Blumenthal, a professor of psychiatry and behavioral sciences at Duke University School of Medicine, in a statement.

One important note: People did not stop taking their blood pressure medications during the study, but because of the reduction they achieved may be able to reduce medications after a discussion with their doctor.

"The most important point is that it is not too late to lower blood pressure by making healthy lifestyle choices," Blumenthal said. "Adopting a healthy lifestyle pays huge dividends, even for people whose blood pressure remains elevated despite being on three or more antihypertensive medications."