For adult males, the recommended daily intake of magnesium varies slightly with age:

• Men aged 19-30 years: 400 mg per day¹.
• Men aged 31 years and older: 420 mg per day¹.

These values cover the general need to meet the requirements of nearly all healthy individuals. It's important to avoid excessive magnesium intake from supplements, as the Tolerable Upper Intake Level (UL) for magnesium from supplements only is 350 mg per day².

Footnotes

1. Office of Dietary Supplements - Magnesium ↩ ↩²

2. The Nutrition Source - Harvard T.H. Chan School of Public Health ↩