There’s no single gram-for-gram formula where a specific amount of potassium “cancels out” a specific amount of sodium. But the research is clear that the ratio between the two matters more than either mineral alone, and most people need significantly more potassium than they’re getting. The World Health Organization recommends consuming less than 2,000 mg of sodium and at least 3,510 mg of potassium per day, which works out to roughly a 1-to-1.75 ratio of sodium to potassium by weight. The American Heart Association goes further for people with elevated blood pressure, recommending 3,500 to 5,000 mg of potassium daily.
Why the Ratio Matters More Than Either Number Alone
Researchers have consistently found that the sodium-to-potassium ratio in your diet is a better predictor of blood pressure problems than how much sodium or potassium you consume individually. A review published in Advances in Nutrition examined both clinical trials and observational studies and concluded that this ratio is the “superior metric” for evaluating blood pressure risk. One large international study (the PURE study, covering multiple countries) found that for every standard increase in the sodium-to-potassium ratio, systolic blood pressure rose by 2.3 mmHg and diastolic by 0.78 mmHg.
The problem is that most people have the ratio backwards. In some populations studied, the average sodium-to-potassium ratio was as high as 4.5 to 1, meaning people consumed far more sodium than potassium. Research from the DASH diet trials shows what happens when you flip that balance: participants who ate a potassium-rich diet while keeping sodium low achieved a sodium-to-potassium ratio of about 0.83 to 1, and saw meaningful blood pressure drops. One study estimated that reaching a 1-to-1 ratio could reduce systolic blood pressure by about 6 mmHg and diastolic by 3 mmHg in people with normal blood pressure.
How Potassium Counteracts Sodium in Your Body
Potassium doesn’t neutralize sodium chemically. Instead, it works through your kidneys. When you eat more potassium, your kidneys respond by flushing more sodium out through urine. This is a direct, measurable effect: higher potassium intake leads to higher sodium excretion. Even when sodium intake is high, adequate potassium helps your body get rid of the excess rather than letting it accumulate and drive up blood pressure.
Beyond this flushing effect, potassium also helps relax blood vessel walls, which further lowers the pressure your blood exerts as it moves through your circulatory system. So potassium fights sodium’s blood pressure effects through two separate pathways: removing sodium from your system and easing the tension in your arteries.
How Much Blood Pressure Actually Drops
The blood pressure benefit of increasing potassium depends heavily on whether you already have high blood pressure. A 2024 dose-response meta-analysis found that boosting potassium intake by about 50 mmol per day (roughly 2,000 mg) lowered systolic blood pressure by 5.3 mmHg in people with hypertension, but only 0.5 mmHg in people without it. Diastolic pressure dropped by 3.6 mmHg in the hypertension group versus just 0.12 mmHg in those with normal readings.
That 5 mmHg systolic drop may sound modest, but at a population level it translates into significant protection. A meta-analysis in the Journal of the American Heart Association found that people with the highest potassium intake had a 13% lower risk of stroke compared to those with the lowest intake. The greatest protection appeared at around 3,500 mg of potassium per day, where stroke risk dropped by as much as 22% in some analyses. The benefit was strongest for the most common type of stroke (ischemic), with a 13% risk reduction.
Practical Targets to Aim For
Putting the research together, here’s what the numbers look like in practice:
- Sodium: Stay under 2,000 mg per day (the WHO target) or under 2,300 mg (the U.S. Dietary Guidelines). Most Americans consume about 3,400 mg daily.
- Potassium: Aim for at least 3,500 mg per day. If you have elevated or high blood pressure, the AHA recommends 3,500 to 5,000 mg daily from food.
- Ratio goal: Try to get your sodium-to-potassium ratio to 1-to-1 or lower. In practical terms, that means eating roughly twice as much potassium (by milligrams) as sodium.
The most effective strategy works both sides of the equation at once: reduce sodium while increasing potassium. Doing just one helps, but doing both is what the DASH diet trials showed produces the most dramatic blood pressure improvements.
Best Food Sources of Potassium
Getting 3,500 to 5,000 mg of potassium from food is achievable but requires deliberate choices. Most potassium-rich foods are whole, unprocessed plant foods, which also tend to be naturally low in sodium. Here are some of the best options:
- Spinach (raw, 1 cup): 454 mg potassium
- Banana (1 medium): about 420 mg potassium
- Sweet potato (½ medium, baked): 229 mg potassium
- White beans (½ cup cooked): about 500 mg potassium
- Avocado (½ fruit): about 485 mg potassium
- Yogurt (1 cup): about 380 mg potassium
A single meal with a baked potato, a side of cooked spinach, and a piece of salmon can deliver well over 1,500 mg of potassium. Fruits, vegetables, beans, dairy, and fish are all reliable sources. The pattern that emerges is simple: the more whole foods you eat and the fewer processed foods, the more favorable your sodium-to-potassium ratio becomes almost automatically. Processed and restaurant foods are where most excess sodium hides, and they rarely contain meaningful potassium.
Why Supplements Aren’t the Best Approach
Over-the-counter potassium supplements are capped at 99 mg per pill by FDA labeling requirements, which is a tiny fraction of the daily target. You’d need 35 to 50 pills to reach adequate intake, and high-dose supplementation carries real risks that food sources don’t.
For people with healthy kidneys, potassium from food poses essentially no danger. The kidneys are efficient at excreting whatever excess comes through diet. The National Academies of Sciences, Engineering, and Medicine reviewed the evidence and concluded there wasn’t enough basis to set an upper limit for dietary potassium in healthy adults. But supplements and potassium-based salt substitutes concentrate the mineral in ways that can overwhelm even healthy kidneys if taken in large amounts, potentially causing dangerous heart rhythm problems.
The risk is especially serious for people with chronic kidney disease or those taking certain blood pressure medications (ACE inhibitors, potassium-sparing diuretics), which impair the kidneys’ ability to clear potassium. For these groups, even normal dietary potassium can sometimes push levels too high. If you’re on these medications, your potassium targets may be different from general recommendations.