Black adults with high blood pressure who received dietitian counseling and home deliveries of groceries consistent with the DASH diet — that is, high in fruits, vegetables, whole grains, low-fat dairy products, nuts, seeds, legumes and lean proteins — had an average overall reduction in systolic blood pressure of 7 mm Hg at three months total and a reduction of 5 mm Hg compared to participants who received only counseling basic diet and a grocery allowance, according to a study presented at the American College of Cardiology Annual Scientific Session (ACC.26).
Participants receiving grocery deliveries also saw a drop in their low-density lipoprotein (LDL) cholesterol levels by 7 mg/dL on average, compared to those receiving a stipend. The findings suggest that programs that increase access to grocery items aligned with the Dietary Approaches to Stop Hypertension (DASH) diet could provide health benefits comparable to those of common blood pressure and cholesterol medications, researchers say.
We are very excited about the magnitude of the effects – they really go beyond what we had anticipated. This study shows a real path forward for self-management in people with hypertension.
Stephen Juraschek, MD, PhD, associate professor of medicine at Harvard Medical School, associate professor of nutrition at Harvard TH Chan School of Public Health, and first author of the study
The study evaluated black adults with hypertension (high blood pressure) living in food deserts where access to fresh produce and high-quality foods is limited. In the United States, hypertension is more common among black adults than any other racial or ethnic group, leading to high rates of cardiovascular disease in this population. About 58% of black adults have hypertension, compared to 48% of the overall U.S. adult population.
Previous studies by Juraschek and colleagues highlight the benefits of adhering to the DASH diet, with one study suggesting that the DASH diet reduces the 10-year risk of atherosclerotic cardiovascular disease by nearly 14% in black adults. For the new study, researchers sought to evaluate the benefits of a DASH intervention in Black adults with hypertension who may have difficulty obtaining DASH-adherent foods.
Researchers recruited 176 participants living in Boston-area communities characterized by lower income and few grocery stores and who had resting systolic blood pressure between 120 mm Hg and 149 mm Hg despite active treatment for hypertension. Participants were on average 60 years old and 80% were women. Half received home-delivered groceries, ordered with personalized advice from a dietitian, while half received a monthly grocery allowance and a brochure explaining the DASH diet. In the group receiving grocery deliveries, dietitians used four principles to help participants prepare grocery lists and plan meals they could cook at home: prepare foods with seasonings other than salt; aim for a potassium-to-sodium ratio of two to one; limit saturated fats to less than 7% of total calories; and follow a DASH eating pattern that also limits processed foods and sugary products, in addition to salt and saturated fat.
“Everyone was able to choose their own groceries for themselves and their family according to DASH principles, with the help of a dietitian,” Juraschek said. “We tried to keep things as general and simple as possible and allow for choice, so people can come up with different combinations to achieve these goals based on their dietary preferences. »
After three months, participants receiving grocery deliveries showed a significantly greater drop in systolic blood pressure compared to the group receiving a grocery allowance, meeting the primary endpoint of the study. Reductions in LDL cholesterol and diastolic blood pressure were also significantly greater in the group receiving grocery deliveries. Between-group differences in systolic blood pressure were also maintained at follow-up measurements taken three months after grocery deliveries and benefits ended.
The findings add to a growing body of evidence highlighting the effects of nutrition on cardiovascular health, as well as the importance of overcoming the barriers some people face in accessing food in order to maintain a heart-healthy diet. The researchers said health insurers, city planners and public health practitioners could focus on policies and programs to make healthy foods more affordable and accessible to improve health and prevent heart disease.
“What’s exciting about a nutritional approach is that not only can it have multiple effects on blood pressure and cholesterol, but it can also be preventative in the future, without some of the side effects or interactions that you might see with some medications,” Juraschek said.
The study was limited to one metropolitan area and lasted only three months. Although the home grocery delivery program has worked well in the Boston area, Juraschek said it may not be feasible in more rural areas. He said further studies could look at longer-term outcomes, additional endpoints for a more detailed picture of cardiovascular health, and outcomes in other high-risk populations such as diabetic patients or those with systolic blood pressure above 150 mm Hg.
The study was funded by the National Institute of Minority Health and Health Disparities of the National Institutes of Health.
This study was simultaneously published online in Natural medicine at the time of presentation.
Juraschek will present the study, “DASH-patterned grocery stores reduce blood pressure in adults with treated hypertension: results from the GoFreshRx randomized clinical trial,” on Saturday, March 28 at 3:45 p.m. CT/8:45 p.m. UTC in the Main Tent of the Great Hall.
