For most adult men, the recommended amount of magnesium per day is about 400–420 mg from all sources (food plus supplements).

Quick Scoop

  • Typical target for men 19–30 years: about 400 mg/day.
  • Men 31+ years: about 420 mg/day.
  • This is the RDA (recommended dietary allowance), meaning an average daily intake that should meet the needs of most healthy men.
  • Many people do not reach this level through diet alone, especially if they eat few whole grains, nuts, seeds, and leafy greens.

From Food vs Supplements

  • Ideally, most magnesium should come from foods like nuts, seeds, whole grains, beans, and leafy greens, which also provide fiber and other beneficial nutrients.
  • For generally healthy adult men, staying around 400–420 mg/day total (diet plus any supplement) is usually sufficient; higher doses from supplements (for example, 500 mg or more per day) can cause diarrhea and, in extreme cases or with kidney problems, magnesium toxicity.

Example Day Hitting ~400–420 mg

A man could roughly reach the RDA with a day like this (numbers approximate):

  • 1 cup cooked spinach.
  • 1 ounce almonds or cashews.
  • 1 cup cooked black beans.
  • 1 serving of whole‑grain cereal or oats.

Together, these kinds of foods can easily total around 300–350 mg, and the rest often comes from other staples like bread, meat, dairy, and additional vegetables.

Safety Notes

  • If you are using a magnesium supplement, many health sources advise not exceeding about 350 mg/day from supplements alone for adults, unless a clinician is guiding you, because very high supplemental doses can be risky.
  • Kidney disease, certain heart conditions, or medications can change what is safe for you, so it is wise to check with a healthcare professional before long‑term high‑dose supplementation.

Bottom line: most healthy adult men should aim for roughly 400–420 mg of magnesium per day from food plus supplements, unless a doctor gives a different target.

Information gathered from public forums or data available on the internet and portrayed here.