How to Choose a Magnesium Supplement
A disciplined buying process beats choosing the bottle with the biggest dose or longest list of forms.
Six checks
1. Clarify why you are considering a supplement. 2. Check elemental magnesium. 3. Understand the form. 4. Review serving size and other ingredients. 5. Look for credible quality/testing information. 6. Check safety and medication considerations.
Don't confuse RDA and supplement upper limit
Recommended intake includes magnesium from all sources. The NIH adult upper limit of 350 mg/day applies to magnesium from supplements and medications, not magnesium naturally present in food.
Sources & next steps
Primary references: NIH Office of Dietary Supplements, Magnesium: Health Professional Fact Sheet and Magnesium: Consumer Fact Sheet. Product details should always be checked against the current merchant label before purchase.