Supplements
Magnesium in supplements · page 171
10,004 supplements on the U.S. market list Magnesium with an amount per serving. The official Tolerable Upper Intake Level for adults is 350 mg a day (supplemental magnesium only (not magnesium in food)).
Tolerable Upper Intake Level (UL)
The highest daily amount that is unlikely to cause harm for almost all healthy people; it applies to supplemental magnesium only (not magnesium in food).
| Age | Men | Women |
|---|---|---|
| 0-6 months | — | — |
| 7-12 months | — | — |
| 1–3 years | 65 mg | 65 mg |
| 4–8 years | 110 mg | 110 mg |
| 9–13 years | 350 mg | 350 mg |
| 14–18 years | 350 mg | 350 mg |
| 19–30 years | 350 mg | 350 mg |
| 31–50 years | 350 mg | 350 mg |
| 51+ years | 350 mg | 350 mg |
Source: NIH ODS Magnesium Fact Sheet for Health Professionals, Table 3 (updated 2026-01-06).
Supplements with Magnesium
10,004 shown · page 171 of 209
Label data: NIH Office of Dietary Supplements, Dietary Supplement Label Database (dsld.od.nih.gov), public domain. Upper limits: NIH ODS Fact Sheets for Health Professionals (values from the Institute of Medicine, Food and Nutrition Board).