Many of the best sources of magnesium and potassium overlap, which makes it straightforward to boost both minerals with the same meals. Dark leafy greens, potatoes, avocados, nuts, beans, and dairy products all deliver meaningful amounts of each. Below is a closer look at the top foods, how much you actually need, and what affects how well your body absorbs these minerals.
Foods High in Both Minerals
Some foods pull double duty, providing substantial potassium and magnesium in a single serving. These are the most efficient choices if you’re trying to increase both at once.
Baked potato: One medium baked potato with the skin delivers about 1,081 mg of potassium and 50 mg of magnesium. That single potato covers roughly a third of an adult’s daily potassium needs.
Cooked spinach: A cup of cooked spinach provides 839 mg of potassium and around 75 mg of magnesium per half cup. Cooking concentrates the minerals because the leaves shrink dramatically.
Avocado: Half a cup of pureed avocado contains about 35 mg of magnesium, and a full avocado supplies roughly 700 mg of potassium. It also delivers healthy fats that support absorption of fat-soluble vitamins.
Plain yogurt (skim): An 8-ounce serving of plain skim yogurt offers 579 mg of potassium and 45 mg of magnesium, making it one of the better dairy options for both minerals.
Peanuts (dry roasted): One ounce gives you 187 mg of potassium and 50 mg of magnesium. Other nuts, especially almonds and cashews, are similarly rich in magnesium.
Raisins: A cup of raisins packs 1,089 mg of potassium and about 25 mg of magnesium per half cup. The sugar content is high, so smaller portions are more practical for most people.
Skim milk: One cup provides 407 mg of potassium and 27 mg of magnesium. Because dairy contains no phytic acid (more on that below), the minerals are well absorbed.
Other Strong Sources Worth Adding
Several foods are standout sources of one mineral and still contribute a useful amount of the other. Black beans, kidney beans, and lentils are rich in both, with a cup of cooked black beans typically supplying over 600 mg of potassium and around 120 mg of magnesium. Edamame, Swiss chard, and pumpkin seeds are also excellent. Pumpkin seeds in particular are one of the most concentrated magnesium sources available, with a single ounce providing over 150 mg.
Bananas get a lot of credit as potassium powerhouses, but a medium banana contains about 451 mg of potassium, which is actually less than a baked potato, a cup of cooked spinach, or even a cup of plain yogurt. Bananas are a fine source, just not the best one.
How Much You Need Each Day
The daily targets for these two minerals differ by an order of magnitude. Adults need far more potassium than magnesium.
- Potassium: 3,400 mg per day for adult men, 2,600 mg for adult women.
- Magnesium: 400 to 420 mg per day for adult men (depending on age), 310 to 320 mg for adult women. Pregnant individuals need 350 to 400 mg.
Most people in the U.S. fall short on both. Potassium is especially hard to hit because the target is so high. Eating several of the foods listed above each day, rather than relying on a single “superfood,” is the most realistic way to get close.
Why These Two Minerals Matter Together
Magnesium and potassium don’t just happen to appear in the same foods. They interact inside your body. Magnesium helps your kidneys regulate how much potassium you retain versus how much you excrete. When magnesium drops too low, your body has a harder time holding onto potassium, which is why low levels of one mineral frequently appear alongside low levels of the other. This relationship also extends to blood pressure: both minerals influence how relaxed or constricted your blood vessels are, and maintaining adequate levels of each supports healthy cardiovascular function.
Low magnesium and low potassium together can cause muscle cramps, tremors, fatigue, weakness, and numbness or tingling in the hands and feet. In more severe cases, deficiency can lead to abnormal heart rhythms. Many people with mild deficiency have no obvious symptoms at all, which makes dietary intake the first line of defense.
What Affects Absorption
Not all of the magnesium listed on a nutrition label ends up in your bloodstream. Whole grains, seeds, legumes, and some nuts contain phytic acid, a compound that binds to magnesium (along with iron, zinc, and calcium) in the gut and reduces how much your body absorbs. This binding only happens when phytic acid is eaten alongside these minerals in the same meal.
Simple preparation steps reduce phytic acid significantly. Soaking beans and grains before cooking, sprouting seeds, and fermenting grains (as in sourdough bread) all break down phytic acid and free up more minerals for absorption. That said, the health benefits of eating whole grains and legumes far outweigh the modest mineral loss from phytic acid, so there’s no reason to avoid these foods. Just vary your sources. Pairing plant-based foods with dairy or animal proteins, which contain no phytic acid, helps balance things out.
Potassium absorption is generally less affected by anti-nutrients. Your body absorbs roughly 85 to 90 percent of the potassium you eat regardless of the source, making it one of the more efficiently absorbed minerals.
Practical Ways to Build These Into Meals
Breakfast is an easy place to start. A cup of plain yogurt with a handful of pumpkin seeds and half a banana delivers a solid dose of both minerals before you leave the house. At lunch, a spinach salad with black beans and avocado covers substantial ground. For dinner, a baked potato with a side of Swiss chard or steamed broccoli adds another layer.
Snacking on dry-roasted peanuts, almonds, or a small portion of trail mix with raisins fills gaps between meals. Smoothies made with spinach, banana, and skim milk or yogurt are another efficient option, especially if you’re not inclined to eat large servings of leafy greens on their own.
The key is variety. No single food delivers enough of either mineral to meet your daily needs, but spreading these options across your meals makes the targets realistic without supplements.