If you’re using this as a health article headline, the claim needs some clarification. Magnesium is an essential nutrient, but supplements aren’t automatically safe for everyone. The two groups that deserve particular caution are people with kidney impairment and people taking certain medications.
Health Experts Warn About Magnesium Supplements: Two Groups Should Be Especially Careful
Magnesium from ordinary foods is generally safe for healthy people because the kidneys remove excess magnesium. The concern is mainly with high-dose supplements and magnesium-containing medicines, such as some laxatives and antacids.
1. People with kidney disease
The kidneys normally eliminate excess magnesium. When kidney function is significantly reduced, however, magnesium can accumulate in the body, particularly when large supplemental doses are taken. Very high magnesium levels can cause low blood pressure, vomiting, weakness, difficulty breathing, abnormal heart rhythms, and, in extreme cases, cardiac arrest.
If you have chronic kidney disease or reduced kidney function, don’t start a magnesium supplement without discussing the dose with your healthcare professional.
2. People taking certain medications
Magnesium can interfere with the absorption of some medicines. For example, it can reduce absorption of oral bisphosphonates and can bind to certain antibiotics, including tetracyclines and quinolones. Some diuretics and long-term acid-reducing medicines can also affect magnesium levels.
A pharmacist or doctor can tell you whether your medication needs to be separated from magnesium or whether supplementation is appropriate at all.
How much is too much?
For adults, the U.S. National Institutes of Health sets an upper limit of 350 mg per day of magnesium from supplements and medications unless a healthcare professional recommends otherwise. This limit doesn’t include magnesium naturally present in food.
Too much supplemental magnesium commonly causes diarrhea, nausea, and abdominal cramping. Extremely high amounts can become dangerous
