Sodium reduction combined with either a typical U.S. diet or the "DASH" diet, which is rich in vegetables, fruit, and low-fat dairy products and low in fat, substantially lowered blood pressure in persons with high blood pressure, according to the results of a study supported by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health (NIH).

The DASH-Sodium study found that the lowest blood pressure levels were in those eating sodium levels much lower than the currently recommended maximum of 2,400 milligrams a day while also eating the DASH (Dietary Approaches to Stop Hypertension) diet. In both the DASH diet and a typical American diet, the lower the sodium, the lower the blood pressure. The combination of following the DASH diet at the lower sodium level reduced blood pressure more than either the DASH diet or lower sodium intake alone.