Ask the doctor: Does potassium lower blood pressure?
Q. I've heard that extra potassium can improve my blood pressure. What do you think?
A. It can in most people. Potassium is a mineral that is essential to health. But, like a lot of essential minerals and vitamins, the question is: how much do we need? Answering that begins with two other questions. First, how much potassium is in your daily diet? (You'd work with a dietitian to answer that one.) Most people in the United States do not eat enough potassium-rich foods, according to the National Health and Nutrition Examination Survey.
Second, do you already have high blood pressure? In people who already have high blood pressure (hypertension) and who don't eat a lot of potassium-rich foods, more dietary potassium definitely lowers blood pressure. In people who do not yet have high blood pressure, eating potassium-rich foods probably protects against getting high blood pressure. People who don't eat a lot of potassium-rich foods are more likely to develop high blood pressure and have a stroke.