Potassium is the single most effective mineral for lowering blood pressure, but magnesium and calcium also play meaningful roles. All three work through different mechanisms, and getting enough of each through your diet can lower systolic blood pressure by several points, sometimes comparable to what a low-dose medication achieves.
Potassium: The Most Impactful Mineral
Potassium lowers blood pressure primarily by helping your kidneys flush out excess sodium. When you eat more potassium, your body excretes more sodium and water, which reduces the volume of fluid in your bloodstream and eases pressure on artery walls. The reverse is also true: when potassium intake drops, your kidneys hold onto sodium. In controlled studies, people on a potassium-restricted diet retained significantly more sodium, gained nearly two kilograms of water weight, and saw their average arterial pressure rise from 82 to nearly 86 mmHg.
The balance between sodium and potassium matters more than either mineral alone. The World Health Organization recommends consuming less than 2,000 mg of sodium and at least 3,510 mg of potassium per day. Research on cardiovascular outcomes suggests that a sodium-to-potassium ratio at or below 1:1 is associated with meaningful reductions in stroke risk. Most people eat far more sodium than potassium, so the practical fix for most diets is to increase potassium while cutting back on salt.
The DASH diet, which emphasizes fruits, vegetables, whole grains, and low-fat dairy, is essentially a mineral-delivery strategy. It’s rich in potassium, magnesium, and calcium while being lower in sodium. In meta-analyses, the DASH diet reduces systolic blood pressure by about 6.7 mmHg and diastolic by about 3.5 mmHg. That’s a clinically significant drop, enough to move some people from stage 1 hypertension back into a normal range.
How Much Potassium You Need
The adequate daily intake for potassium is 3,400 mg for adult men and 2,600 mg for adult women. Most Americans fall well short of this. High-potassium foods include baked potatoes with skin, bananas, black beans, spinach, avocado, and plain yogurt. A single baked potato delivers around 900 mg, making it one of the most potassium-dense everyday foods.
Potassium supplements and salt substitutes (which replace sodium chloride with potassium chloride) can be dangerous for people with kidney disease, diabetes, or heart failure. These conditions impair the body’s ability to clear potassium from the blood, and excess levels can cause life-threatening heart rhythm problems. The same risk applies if you take ACE inhibitors, beta-blockers, or certain anti-inflammatory medications. For most people with healthy kidneys, getting potassium from food is both safe and effective.
Magnesium: A Natural Vessel Relaxer
Magnesium lowers blood pressure by relaxing the smooth muscle in artery walls. It works like a mild, natural version of the calcium-channel-blocking drugs that cardiologists prescribe. When magnesium levels outside your cells rise, calcium levels inside the muscle cells of your arteries drop, causing those muscles to relax and the vessels to widen. Wider vessels mean lower pressure.
A 2024 meta-analysis of 38 randomized controlled trials involving over 2,700 participants found that magnesium supplementation reduced systolic blood pressure by about 2.8 mmHg and diastolic by about 2 mmHg on average. But the effect was much larger in two groups: people already taking blood pressure medication saw an additional systolic drop of nearly 7.7 mmHg, and people with low magnesium levels saw a systolic reduction of about 6 mmHg. In people with normal blood pressure, the effect didn’t reach statistical significance. The median dose across studies was 365 mg of elemental magnesium, taken for about 12 weeks.
The recommended daily allowance for magnesium is 420 mg for adult men and 310 to 320 mg for women. The richest food sources by serving size are pumpkin seeds (156 mg per ounce), chia seeds (111 mg per ounce), almonds (80 mg per ounce), and cooked spinach (78 mg per half cup). Cashews, black beans, edamame, and peanut butter are also solid sources. Brown rice has four times the magnesium of white rice, and whole wheat bread has more than double that of refined versions.
Calcium’s Smaller but Real Effect
Calcium contributes to blood pressure regulation, though its effect is more modest. A Cochrane review of 18 trials with over 3,100 participants found that increasing calcium intake lowers systolic blood pressure by about 1.4 mmHg and diastolic by about 1.5 mmHg. The effect was dose-dependent: intakes above 1,500 mg per day produced a systolic reduction of about 2.8 mmHg, roughly double the effect seen at lower doses. Younger adults (under 35) also saw a larger benefit than older adults.
The recommended daily intake for calcium is 1,000 mg for most adults, rising to 1,200 mg for women over 30 and men over 70. Dairy products, fortified plant milks, sardines, tofu made with calcium sulfate, and leafy greens like kale and bok choy are reliable sources. Because the blood pressure benefit of calcium is relatively small, it’s best viewed as one piece of a broader mineral strategy rather than a standalone solution.
Trace Minerals: Selenium and Manganese
Beyond the big three, some trace minerals show early associations with blood pressure. In a longitudinal study of over 250 adults, people with selenium levels in the highest quartile experienced yearly decreases of about 1 mmHg systolic and 0.7 mmHg diastolic. Mid-range blood manganese levels were associated with similar small annual declines. These effects appear to depend on specific concentration ranges rather than a simple “more is better” pattern, and the evidence is far less developed than for potassium, magnesium, or calcium. Supplementing trace minerals specifically for blood pressure isn’t supported by current evidence.
Putting It All Together
No single mineral is a substitute for blood pressure medication if you need it, but collectively, getting enough potassium, magnesium, and calcium from your diet can make a real difference. A day’s eating that includes a banana, a handful of pumpkin seeds, a serving of black beans, a baked potato, a cup of yogurt, and a salad with spinach covers a large portion of your daily targets for all three minerals while also being naturally low in sodium.
The sodium-to-potassium ratio is the single most actionable number to think about. Processed and restaurant foods drive sodium intake up while providing little potassium. Whole, minimally processed foods do the opposite. Shifting that balance is, for most people, the most effective dietary change for blood pressure and doesn’t require supplements, special products, or complicated meal plans.