Everyday Foods Rich in Both Magnesium and Potassium

Most people think of the banana when someone mentions potassium. But several common kitchen foods deliver both magnesium and potassium together — and that combination matters far more than either mineral alone when it comes to supporting healthy blood pressure and circulation.

By Marion Ellis

Health & Wellness Desk · Updated November 2026 · 7 min read

Magnesium and potassium are the two minerals that consistently appear in conversations about healthy blood pressure and circulation. They're both abundant in whole plant foods, they work together in the body, and most Americans get less than the recommended amounts of either. The good news: a handful of everyday kitchen staples deliver both at once.

If you're thinking about where to start — and you're tired of hearing "eat a banana" — this is the practical list that nutrition researchers actually recommend, with specific amounts per serving based on USDA FoodData Central data.

Why These Two Minerals Are Usually Discussed Together

Potassium and magnesium don't just happen to appear in the same foods. They interact in the body in ways that make their combined presence more meaningful than either alone.

Potassium's most recognized role in vascular health is counterbalancing sodium. When dietary potassium is adequate, the kidneys excrete more sodium, which reduces the amount of fluid the body retains and supports healthy blood vessel tone. This is why dietary guidelines consistently recommend eating potassium-rich foods as part of a blood-pressure-friendly eating pattern.

Magnesium supports the relaxation of smooth muscle in blood vessel walls and plays a role in more than 300 enzymatic reactions throughout the body, many of them linked to cardiovascular and metabolic function. Research published by the NIH suggests that lower dietary magnesium intake is associated with less optimal blood pressure patterns in population studies.

"Both potassium and magnesium play important roles in healthy blood pressure. Diets rich in these minerals — found in fruits, vegetables, legumes, and whole grains — are consistently associated with cardiovascular health benefits." — NIH Office of Dietary Supplements

The claim that applies here is structural and factual: both minerals support healthy blood pressure levels that are already within the normal range. This is not a treatment claim for hypertension — if you have elevated blood pressure or take medication, all dietary changes should be discussed with your healthcare provider first.

Source: NIH Office of Dietary Supplements — Potassium: Health Professional Fact Sheet

The Kitchen List: Foods That Have Both

All amounts below are from USDA FoodData Central. "Cooked" refers to standard boiling or steaming unless noted.

Source: USDA FoodData Central — nutrient composition data

The Foods Worth Highlighting — and Why

Cooked leafy greens (spinach, Swiss chard). Cooking concentrates these greens dramatically — a cup of cooked spinach started as about 10 cups raw. The magnesium and potassium content per cup cooked is among the highest of any single food. The oxalates in raw spinach slightly reduce mineral absorption; cooking reduces oxalate content, making cooked versions more bioavailable for these two minerals.

Pumpkin seeds. Ounce for ounce, pumpkin seeds (pepitas) are one of the most concentrated magnesium sources in the food supply. A single ounce delivers about 37% of the daily RDA for magnesium. They're calorie-dense, so a small handful goes a long way. Add to yogurt, oatmeal, or eat as a snack.

Avocado. Avocado is one of the few fruits with a genuinely substantial potassium content — a medium avocado has more potassium than a banana. It also delivers a moderate but meaningful dose of magnesium, along with heart-supportive monounsaturated fats. It's one of the most versatile dual-source options in everyday cooking.

Legumes (black beans, lentils, edamame). Legumes are among the most reliable, affordable, and consistent sources of both minerals. A cup of cooked black beans covers roughly 30% of daily magnesium needs and nearly 20% of potassium needs. They're also high in fiber, which supports vascular health independently.

Source: Harvard T.H. Chan School of Public Health — The Nutrition Source: Vegetables and Fruits

What About the Banana?

Bananas deserve their reputation as a potassium source: a medium banana provides about 422 mg of potassium, roughly 12% of the daily Adequate Intake. That's genuinely useful. But magnesium? A medium banana contains about 32 mg — around 8–10% of the daily RDA. Good, but not in the same league as pumpkin seeds, spinach, or black beans for dual coverage.

The banana earned its cultural prominence as a "potassium food" partly because it's a recognizable, portable, easy-to-remember reference point. But if you're specifically looking for foods that deliver both minerals in one serving, the list above offers more efficient options across a wider variety of meals.

Building a Pattern Around These Foods

The goal isn't to eat spinach at every meal or add pumpkin seeds to everything. The practical approach is to identify two or three dual-source foods you already enjoy and find regular places for them in your existing eating pattern. Some examples:

Add a handful of pumpkin seeds to morning oatmeal or yogurt. Use cooked black beans or lentils as a base for one lunch per week. Swap sweet potato for white potato two or three times a week. Use avocado on toast or in salads where you'd otherwise use something with less nutritional value. Add a bag of frozen spinach to soups and sauces — it disappears into most dishes without changing the flavor.

These small substitutions, repeated consistently, add up to a meaningfully different mineral intake over weeks and months.

What the Research Actually Says (Without Overstating It)

Population studies consistently show that people who eat diets high in fruits, vegetables, and legumes — the same foods high in both magnesium and potassium — tend to have better blood pressure patterns than people who don't. What those studies can't do is prove that it's specifically the magnesium or potassium in those foods causing the effect, versus the fiber, the reduced processed food intake, or dozens of other variables.

What the NIH says about each mineral specifically is more precise: adequate potassium intake is associated with supporting blood pressure already within the normal range, particularly when sodium intake is also moderate. Adequate magnesium intake is associated with normal vascular tone. Neither is a drug. Neither treats hypertension. And both are more effective in the context of an overall dietary pattern than as isolated interventions.

If your blood pressure is elevated or you're on medication for it, talk to your healthcare provider before making significant dietary changes. Food is powerful, but it works in context — not in isolation.

Source: NIH Office of Dietary Supplements — Magnesium: Health Professional Fact Sheet