# Dietitians Reveal the Number-1 Sign You're Taking Too Much Magnesium
Magnesium supports muscle function, bone health, and energy production, making it a popular supplement. But exceeding safe levels creates real risks that dietitians want people to recognize.
The primary warning sign of magnesium overdose is loose stools or diarrhea. Registered dietitian nutritionists explain that excess magnesium pulls water into the intestines, triggering digestive distress. This happens because your body cannot absorb unlimited amounts of the mineral, so surplus magnesium passes through your digestive tract unabsorbed.
Magnesium toxicity rarely occurs from food sources alone. It develops primarily when people take supplements without proper guidance or exceed recommended daily intakes. The National Institutes of Health sets the upper safe limit at 350 milligrams daily from supplements for adults, though dietary sources don't count toward this cap.
Beyond diarrhea, serious overdose symptoms include nausea, muscle weakness, and irregular heartbeat. In severe cases, extremely high magnesium levels can cause confusion, low blood pressure, and cardiac problems. People with kidney disease face particular danger, since kidneys regulate magnesium excretion.
Dietitians recommend checking your total magnesium intake from all sources. Many multivitamins contain magnesium. Antacids and laxatives often include it as an active ingredient. Adding a standalone supplement on top of these products can quickly push you over safe limits.
Most people obtain adequate magnesium from foods like spinach, almonds, pumpkin seeds, and black beans. Before starting any magnesium supplement, registered dietitian nutritionists advise consulting your healthcare provider, especially if you take medications or have underlying health conditions.
The key takeaway for supplement users: magnesium