A combination of reduced sodium intake and the DASH diet lowers blood pressure in adults with hypertension, according to preliminary research presented at the American Heart Association's Scientific Sessions 2017, a premier global exchange of the latest advances in cardiovascular science for researchers and clinicians.

The study followed 412 adults with systolic blood pressures in four categories: less than 130 mmHg; between 130 and 139 mmHg; between 140 and 159 mmHg; and 150 or higher mmHg. They were either on low-sodium or DASH (Dietary Approaches to Stop Hypertension) diets for four weeks. DASH diets are rich in fruits, vegetables, and whole grains along with low or fat-free dairy, fish, poultry, beans, seeds and nuts. The DASH dietary pattern is promoted by the U.S.-based National Heart, Lung, and Blood Institute and the American Heart Association to control hypertension. While both low-sodium and DASH diets have been reported to help lower high blood pressure, this study examines the effects of combining the two diets in adults with high blood pressure.

Researchers found:

Participants who cut their sodium intake had lower systolic blood pressure than adults that had high sodium consumption.

Participants who followed the DASH diet but did not reduce their sodium intake also had lower blood pressure than those with similar sodium intake but not on the DASH diet.

Participants on the combined diet had lower blood pressure compared to participants with high sodium intake eating their regular diet.

The reduction in blood pressure increased with the severity of hypertension, with participants having systolic blood pressure over 150 mmHg showing the most dramatic difference with the low sodium-DASH diet than those not on the diet. More research is needed to determine if the combination diet has the same effect for adults with systolic blood pressure above 160 mmHg.