Magnesium
Muscle and nerve function, blood sugar control.
Some good studies
- You need a day
- 310 mg women 19 to 30 (men 19 to 30: 400 mg; age 31 and over: women 320 mg, men 420 mg)
- Most pills have
- 300 mg
- Safe max a day
- 350 mg supplemental magnesium only, adults (does not count magnesium from food)
- Careful studies
- 561 26 in 2025, 20 in 2015
Photo: Ron LachWhat the research says
The short version
Magnesium supports hundreds of enzyme reactions, including muscle, nerve and blood sugar control. Trials show supplements lower blood pressure only slightly, and evidence for diabetes control and migraine is limited or mixed.
Supplement doses above 350 mg a day often cause diarrhea and cramps, and magnesium can interact with some antibiotics and oral bisphosphonates.
About "most pills": NIH ODS cites a review suggesting 300 mg twice a day for migraine prevention; ODS also says supplements carrying the FDA health claim must provide 84 to 350 mg per serving.
Sources: ods.od.nih.gov
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