Potassium from Food may Control Blood Pressure

A new study shows that increasing dietary potassium might keep blood pressure in check - especially in African Americans. Controlling salt intake has been the mainstay recommendation for blood pressure control. The study, from the American Society of Nephrology suggests that getting more potassium may be as important as limiting salt intake. The research is presented at the American Society of Nephrology's 41st Annual Meeting and Scientific Exposition in Philadelphia, Pennsylvania.

Susan Hedayati, MD, of the University of Texas Southwestern Medical Center in Dallas, Texas, and the Dallas VA Medical Center, led the study, which also identified a gene that may have a direct influence on how potassium affects blood pressure.

Data from the Dallas Heart Study was analyzed, involving 3,300 subjects, half of whom were African American. The amount of potassium found in urine samples directly correlated with the incidence of high blood pressure. "The lower the potassium in the urine, hence the lower the potassium in the diet, the higher the blood pressure. This effect was even stronger than the effect of sodium on blood pressure, “says Dr. Hedayati. The results remained the same despite age, race, cholesterol readings, risk factors for heart disease, diabetes and smoking.

Dr. Chou-Long Huang, a co-author of this study uncovered the role of the gene, called WNK1, finding that it might be responsible for the effect of potassium on blood pressure. The researchers are exploring the gene further to determine exactly what activity it provides to lower blood pressure when potassium is included in the diet. They plan further studies involving participants on a fixed amount of dietary potassium.

Dr. Hedayati says efforts should be made to lower dietary intake of salt, while increasing potassium. Bananas, citrus fruits, and vegetables are all good dietary sources of potassium. Eat your fruits and vegetables throughout the day, making sure you get five or more servings daily. Diabetics should limit starchy vegetables to smaller portions.

Low Potassium Linked to High Blood Pressure