Minerals · Food Sources

The Everyday Vegetables Highest in Magnesium (With Amounts)

Cooked spinach leads at 78 mg per half cup. After that the list surprises most people — it includes edamame, Swiss chard, black beans, and even a baked potato. Here is the full ranking by serving, and why the magnesium–potassium pair is the one combination most worth building around.

By Marion Ellis

Nutrition Desk · Updated November 2026 · 8 min read

People who start paying attention to magnesium quickly discover that most of the foods they already know about — spinach, beans, broccoli — vary enormously in how much they actually deliver per serving. Broccoli, for instance, is excellent for many things but relatively modest on magnesium at about 11 mg per half cup raw. Cooked spinach, by contrast, packs 78 mg into the same half-cup measure.

The goal of this piece is simple: give you the actual numbers by serving size, drawn from NIH Office of Dietary Supplements data, so you can make informed choices rather than guessing from reputation.

The Ranking: Vegetables by Magnesium per Serving

All amounts below are from the NIH ODS magnesium fact sheet (health professional version), which cites USDA nutrient data. The daily value (DV) is based on 420 mg for adults. Cooking typically concentrates the minerals in leafy greens because water is released, increasing the milligrams per volume.

Note: “~” indicates an approximation; Swiss chard values are consistent across USDA data but are cited less prominently in the NIH ODS summary table than spinach. For precise values, the USDA FoodData Central database is the authoritative source.

Why Cooked Spinach Leads the List

Raw spinach has reasonable magnesium content, but most of it is locked inside cell walls that are hard for the digestive system to break down efficiently. Cooking ruptures those cell walls, releasing the minerals and — because water is expelled from the leaves during cooking — dramatically increasing the concentration per volume. A cup of raw spinach wilts to roughly a quarter cup when cooked, so you are eating four times as much leaf material per measure.

The same principle applies to Swiss chard, kale, and other leafy greens: cooked is almost always a better delivery vehicle for magnesium per serving than raw, even though both are nutritious choices.

The Magnesium–Potassium Pair for Healthy Circulation

Once you start tracking magnesium in food, something becomes apparent quickly: many of the best sources also happen to be excellent potassium sources. Spinach, edamame, avocado, beans, and baked potato are all in the top tier of potassium foods as well.

This is not a coincidence in terms of nutrition importance. The American Heart Association dietary guidance and the NIH-designed DASH (Dietary Approaches to Stop Hypertension) eating plan both emphasize this mineral pair. Magnesium supports relaxation of the smooth muscle tissue in blood vessel walls. Potassium helps the body manage sodium balance and fluid distribution. Together, diets naturally rich in both are consistently associated with healthy blood pressure levels and healthy circulation.

For adults 45 and older who are building a plate with this in mind, the practical implication is that targeting the same foods handles both minerals simultaneously — no need to optimize separately.

How Much Magnesium Do Adults Need?

The NIH ODS sets the Recommended Dietary Allowance (RDA) for magnesium at 420 mg/day for adult men and 320 mg/day for adult women. Survey data consistently shows that a large percentage of US adults consume less than these targets from food alone.

Meeting the RDA through vegetables and other whole foods is achievable but requires deliberate choices:

• Half a cup of cooked spinach at lunch (78 mg)
• Half a cup of edamame as a snack (50 mg)
• A baked potato with skin at dinner (43 mg)
• An ounce of almonds (80 mg)

That combination alone delivers 251 mg — about 60% of the men’s RDA and nearly 80% of the women’s. Adding brown rice (42 mg per half cup cooked) or pumpkin seeds (156 mg per ounce) closes the gap further.

For adults 45 and older, absorption efficiency from food can decline modestly with age. Some choose a magnesium supplement to complement dietary sources rather than relying on vegetables alone to close the gap.

Practical Notes on Getting More Magnesium From Vegetables

• Keep the cooking liquid. When you boil leafy greens, some magnesium leaches into the water. Steaming, sautéing, or using the cooking water in a sauce preserves more of it.
• Leave the skin on the potato. The majority of a potato’s mineral content sits in and just beneath the skin. Peeling discards most of it.
• Pair with vitamin D and avoid high-dose zinc. Vitamin D facilitates magnesium absorption. High-dose zinc supplements (above 142 mg per day) can interfere with magnesium uptake — not a concern at typical dietary zinc levels.
• Watch alcohol intake. Chronic alcohol consumption increases urinary excretion of magnesium and is a recognized contributor to deficiency in population studies.
• Frozen spinach is equivalent to fresh for minerals. Freezing does not degrade the magnesium content. Frozen spinach is more concentrated by weight (less air and water) and often costs less, making it a practical choice for daily use.

When Food Is Not Enough

Even with consistent meal planning, some people find it difficult to reliably reach their magnesium target from food alone — particularly if caloric intake is restricted, food variety is limited, or gut absorption is not optimal.

Of the supplements reviewed while preparing this article, VitalFlush was notable for its formulation. It is designed specifically to support healthy blood pressure levels already within the normal range and healthy circulation — two of the main reasons adults 45+ begin paying closer attention to their magnesium intake. It is manufactured in GMP-certified facilities in the USA and comes with a 60-day guarantee.

The claim it makes — that it “supports healthy blood pressure levels already within the normal range” — reflects the supplement standard: it describes support for normal function, not treatment of a diagnosed condition. It is not a substitute for a physician-supervised approach to cardiovascular health, and it does not replace the dietary patterns discussed above.