Many common vegetables are good sources of magnesium, with leafy greens and beans topping the list. A single cup of cooked black beans delivers about 91 mg of magnesium, and cooked spinach provides roughly 157 mg per cup. Most adults need between 310 and 420 mg of magnesium per day, so a few smart vegetable choices can cover a significant chunk of that target.
Beans and Legumes Lead the Pack
If you’re looking for the biggest magnesium payoff per serving, beans are hard to beat. A cup of cooked black beans provides around 91 mg, while cooked lima beans deliver 101 to 126 mg per cup depending on the variety. Black-eyed peas come in at about 86 mg per cooked cup, and a cup of edamame gives you roughly 50 to 72 mg. Even green peas, which most people think of as a basic side dish, contribute 48 mg per cup raw.
Canned beans retain most of their magnesium. A cup of canned black beans still provides about 84 mg, making them a convenient option when you don’t want to cook dried beans from scratch.
Leafy Greens Are Especially Rich
Spinach is one of the most magnesium-dense vegetables you can eat, with raw spinach containing about 2,300 mg per kilogram. Swiss chard, beet greens, and kale are also strong sources, though spinach consistently ranks highest among cooking greens. The deep green color is a useful visual cue: chlorophyll, the pigment that makes leaves green, has a magnesium atom at its center, so darker greens generally contain more of the mineral.
There’s one important catch with spinach. It’s also high in oxalates, compounds that bind to magnesium and calcium in your digestive tract and form insoluble complexes your body can’t absorb. This means you don’t actually take in all the magnesium listed on a nutrition label for spinach. You still absorb a meaningful amount, but pairing spinach with other magnesium sources rather than relying on it alone is a smarter strategy.
Other Vegetables Worth Adding
Beyond greens and beans, several everyday vegetables contribute moderate amounts of magnesium. Pumpkin and other winter squashes, potatoes (especially with the skin on), green peppers, and carrots all contain the mineral. Green peppers provide roughly 1,800 mg per kilogram raw, and pumpkin about 1,200 mg per kilogram. These aren’t blockbuster numbers per serving, but they add up when you’re eating a varied diet.
Snow peas and sugar snap peas offer around 24 to 33 mg per cup. Green beans are more modest at about 26 mg per cooked cup. These won’t single-handedly move the needle, but combined with higher-magnesium vegetables, they contribute to your daily total in a meaningful way.
How Much You Need Each Day
The recommended daily intake for magnesium varies by age and sex. Adult men aged 19 to 30 need 400 mg per day, rising to 420 mg after age 31. Women in the same age ranges need 310 mg and 320 mg, respectively. Teenagers actually need surprisingly high amounts: 410 mg for boys and 360 mg for girls aged 14 to 18.
Falling short of these targets is common. Early signs of low magnesium include muscle cramps, fatigue, weakness, and numbness. Severe deficiency can cause convulsions and abnormal eye movements, though this level of depletion is rare from diet alone.
Cooking Methods Affect How Much You Get
Boiling vegetables causes magnesium to leach into the cooking water. The losses vary by vegetable, but they can be significant. Spinach loses about 31% of its magnesium when boiled, dropping from 2,300 mg/kg raw to roughly 1,589 mg/kg after boiling. Pumpkin loses about 21%, and green peppers lose around 27%. Carrots hold up better, losing only about 6%.
If you want to retain the most magnesium, steaming or roasting your vegetables is a better bet than boiling. When you do boil, using the cooking liquid in a soup or sauce recaptures some of that lost mineral. Stir-frying with minimal liquid is another good option.
Why Today’s Vegetables May Have Less
The magnesium content of produce has been gradually declining over the past several decades, and modern farming practices are a big reason why. Intensive agriculture pulls large quantities of magnesium from the soil with each harvest, but standard fertilizers replace only nitrogen, potassium, and phosphorus. Over time, this creates a negative magnesium balance in the soil.
Heavy use of potassium fertilizer makes the problem worse. Potassium competes directly with magnesium for uptake by plant roots, and since plants have specialized transport systems for potassium but only nonspecific ones for magnesium, potassium wins that competition. Rising atmospheric carbon dioxide adds another layer: elevated CO2 has been shown to decrease magnesium concentrations in the edible parts of vegetables. Soil acidity, which is increasing in many agricultural regions, further reduces magnesium availability to crops.
None of this means vegetables are no longer good sources. It does mean that eating a wide variety of magnesium-rich vegetables, rather than depending on a single one, gives you the best shot at meeting your daily needs.