Salt, potassium, and blood pressure
Most advice stops at “eat less salt.” The biggest recent trial suggests the swap may matter as much as the cut.
The short version
- Too much sodium raises blood pressure in most people.
- Potassium works in the opposite direction, helping the body get rid of sodium.
- Swapping regular salt for a potassium-blend salt cut strokes by 14% in a 21,000-person trial.
How sodium and potassium push against each other
Sodium makes your body hold onto water, which raises the volume in your blood vessels and the pressure inside them. Potassium helps your kidneys flush sodium out and helps vessel walls relax. Most people eat far more sodium than potassium.
The salt substitute trial
The Salt Substitute and Stroke Study (SSaSS) gave about 21,000 people in 600 villages in rural China either regular salt or a blend of 75% sodium chloride and 25% potassium chloride. Everyone had a past stroke or was over 60 with high blood pressure. Over about five years, the salt-substitute group had 14% fewer strokes, 13% fewer major heart and stroke events, and 12% fewer deaths.
Who should be careful
Potassium-blend salt isn’t for everyone. The trial excluded people with kidney disease and people taking potassium-sparing diuretics or potassium supplements, because extra potassium can be dangerous for them. If either applies to you, ask your doctor first.
Food sources of potassium
Potatoes, beans, lentils, bananas, spinach, avocados, yogurt, and tomatoes. Most sodium comes from packaged and restaurant food, not the salt shaker.
Sources
Educational information, not medical advice. Read our medical disclaimer.