For millions of adults managing high blood pressure with medications that can elevate potassium, the Dietary Approaches to Stop Hypertension (DASH) diet has long been a recommended lifestyle intervention. But a lingering concern has been whether the diet's potassium-rich foods might push blood potassium to dangerous levels, especially in those taking drugs known to retain potassium. Preliminary research presented at the American Heart Association's Hypertension Scientific Sessions 2026 now offers strong reassurance: the DASH diet did not cause harmful changes in potassium levels or kidney function in this population.
The study, a secondary analysis of the GoFresh and GoFreshRx randomized trials, examined 356 Black adults in the Boston area with high blood pressure. Half received three months of DASH-patterned groceries and nutrition counseling, while the other half received a stipend to buy their own groceries. Researchers measured blood potassium at baseline and after 12 weeks. The average baseline serum potassium was normal (4.16 mmol/L in the grocery group and 4.18 mmol/L in the stipend group). Critically, among those taking ACE inhibitors, angiotensin receptor blockers, potassium-sparing diuretics, beta blockers, and non-steroidal anti-inflammatory drugs (NSAIDs), potassium levels did not rise to dangerous levels.
This matters because hyperkalemia—elevated blood potassium—can disrupt heart rhythm and is a particular risk for people with impaired kidney function. Many common medications for hypertension, heart failure, and Type 2 diabetes can increase potassium retention. As a result, some clinicians have hesitated to recommend the DASH diet to patients on these drugs. The new findings suggest that hesitation may be unwarranted for those with normal baseline potassium and preserved kidney function.
"Knowing that the DASH diet did not increase blood potassium levels in this population with normal baseline potassium levels provides assurance that the DASH diet can be prescribed to a wide range of people," said Marian Budu, M.B.B.S., M.P.H., a clinical research coordinator at Beth Israel Deaconess Medical Center and presenting author.
The DASH diet emphasizes fruits, vegetables, whole grains, nuts, and low-fat dairy, and limits red meat, salt, and added sugars. It aligns with the American Heart Association's 2026 Dietary Guidance to Improve Cardiovascular Health. The grocery intervention provided about 4,700 mg of potassium daily with a 2:1 potassium-to-sodium ratio.
"This follow-up study is important because it confirms that significant increases in potassium did not occur with the DASH diet, even for patients on medications that might contribute to increased potassium levels," said Kevin Volpp, M.D., Ph.D., scientific lead of the Association's Health Care by Food initiative, who was not involved in the study.
However, the study had limitations: it excluded people with stage 4 or 5 kidney disease or elevated baseline potassium, and enrolled only Black adults in Boston, so results may not generalize. The authors call for future research in those with suboptimal kidney function and higher baseline potassium. The findings are considered preliminary until published as a full manuscript. The abstracts will appear in the Hypertension Scientific Sessions 2026 Supplement of the journal Hypertension. For more on potassium and heart health, see the Association's A Primer on Potassium. Additional resources include Following 9 key steps for a lifetime of eating well can support heart health and Reducing sodium in everyday foods may yield heart-health benefits across populations. The full release is available at www.newmediawire.com.
