If you're a middle-aged adult with slightly high blood pressure, peeing out more potassium might mean you have a lower chance of heart disease — one study found a 36% lower risk for those with the highest levels, but the result wasn't strong enough to be sure it wasn't just by chance.

If you're a middle-aged adult with slightly high blood pressure, having more sodium than potassium in your body may raise your chances of heart disease by 24% for every unit increase in the balance — and this combo predicts heart problems better than either mineral alone.

For people who already have heart disease, the more potassium their body gets rid of in urine, the more likely they are to have a heart attack, stroke, or die — which is the opposite of what most people think potassium does.

For people with slightly high blood pressure between 30 and 54 years old, how much salt they eat — measured by what shows up in their urine — doesn’t seem to clearly raise their risk of heart disease when looked at on its own.

For people with heart disease, the more potassium their body gets rid of in urine, the higher their blood pressure tends to be — every extra gram of potassium excreted per day raises systolic pressure by about 1 point and diastolic by about 0.6 points, which is the opposite of what doctors usually expect.

For people who already have heart disease, having just the right balance of salt and potassium in their urine — not too much, not too little — seems to be linked to the lowest chance of heart problems or dying from any cause. Too little or too much of this balance is linked to higher risks.