Nutrient glossary

What is magnesium?

Magnesium is a helper mineral in over 300 enzyme reactions, from muscle contraction and sleep to blood sugar control.

Reviewed 20 July 2026. General information, not medical advice.

The short version

Magnesium is quietly involved in almost everything: making energy from food, steadying nerve and muscle signals, building bone and regulating blood sugar. Intakes tend to slide because its best sources, whole grains, nuts, seeds and greens, are exactly what processed diets crowd out.

Refining strips it: white flour keeps only about a quarter of the wheat grain’s magnesium. Choosing whole versions is most of the battle.

Daily reference

300 mg a day

The reference is 300 mg a day for men and 270 mg for women.

This is the fixed adult reference used across these pages. In the app, your amount adjusts to your body and way of eating.

Best food sources of magnesium

Full ranking
FoodPer servingPer 100g
Hemp Seeds210 mg700 mg
Pumpkin Seeds166 mg592 mg
Black Beans (cooked)120 mg70 mg
Quinoa (cooked)118 mg64 mg
Mackerel107 mg97 mg
Sunflower Seeds91 mg325 mg
Buckwheat86 mg51 mg
Cannellini Beans82 mg63 mg

Common questions

Do magnesium supplements help sleep?
Evidence is modest and mostly in people who were low to begin with. Correcting a genuinely low intake helps; adding more on top of enough does not.
What are the best food sources of magnesium?
Pumpkin seeds, chia, almonds, cashews, whole grains, beans and dark leafy greens lead the table.