Health experts are urging caution with magnesium supplements, especially among people with certain medical conditions. Magnesium is an essential mineral involved in muscle function, nerve signaling, heart rhythm, and bone health, but taking extra magnesium is not risk-free for everyone.
Two High-Risk Groups Who Should Be Especially Careful
1. People with Kidney Problems
The kidneys help remove excess magnesium from the body. If kidney function is reduced, magnesium can build up in the blood, potentially causing high magnesium levels (hypermagnesemia).
Possible warning signs include:
- Nausea or vomiting
- Muscle weakness
- Extreme tiredness
- Low blood pressure
- Confusion
- Irregular heartbeat
- In severe cases, breathing problems
People with chronic kidney disease should talk with a healthcare professional before using magnesium supplements.
2. Older Adults Taking Multiple Medications
Older adults are more likely to have reduced kidney function and may take several medicines that can interact with supplements.
Magnesium supplements may interfere with absorption of some medications, including certain:
- Antibiotics
- Thyroid medications
- Osteoporosis medicines
Spacing supplements and medications may be necessary, but the timing depends on the specific medicine.
Other Things to Know About Magnesium Supplements
- Many people can meet magnesium needs through foods such as nuts, seeds, legumes, whole grains, and leafy green vegetables.
- High doses of supplemental magnesium commonly cause diarrhea, stomach cramps, and nausea.
- The amount of magnesium that is appropriate depends on age, health status, diet, and medications.
When to Ask a Healthcare Professional Before Taking Magnesium
Consider getting medical advice first if you:
- Have kidney disease
- Are over age 65
- Take several prescription medications
- Have heart rhythm problems
- Are considering high-dose magnesium products
Magnesium can be beneficial when someone has a deficiency or a specific medical reason to take it, but more is not always better—especially for people whose bodies may have difficulty clearing excess amounts.
