Taking Too Many of These Mineral-Rich Supplements Could Cause Health Troubles

While we should always try to meet our dietary needs with food alone, vitamin and mineral supplements can help fill in nutritional gaps. In particular, you may benefit from taking a magnesium supplement. This essential nutrient is involved in so many bodily systems — it regulates muscle function and blood pressure and keeps our bones strong. But how much is too much? Consuming this mineral in excess could lead to magnesium toxicity, which can cause side diarrhea, nausea, and stomach cramps. 

To learn more about magnesium toxicity and how much of this essential mineral we should really be taking, we spoke with Carol Haggans, MS, RD, scientific and health communications consultant with the Office of Dietary Supplements (ODS).

Can a person take too much magnesium?

Although we often see magnesium in supplement form, it is naturally found in foods such as green leafy vegetables, legumes, nuts, seeds, and whole grains. Haggans notes that magnesium-rich foods are safe to consume in any amount, so people don’t have to limit their intake. However, the same can’t be said about magnesium supplements.

“Magnesium toxicity can occur if someone gets very high amounts of magnesium from dietary supplements or medications (some medications like laxatives and antacids contain magnesium),” she explains. “It can also occur if someone has impaired kidney function because their body is unable to remove excess magnesium.”

What happens when you take too much magnesium? You may experience stomach cramps, diarrhea, and nausea, as mentioned above. Haggans also provided a list of more severe side effects of magnesium toxicity. You will need immediate medical attention if you experience any of these:

• Low blood pressure
• Nausea
• Vomiting
• Facial flushing
• Retention of urine
• Ileus (bowel obstruction)
• Depression and lethargy before progressing to muscle weakness
• Difficulty breathing
• Extremely low blood pressure
• Irregular heartbeat
• Cardiac arrest

With these symptoms in mind, it’s important not to go overboard with a supplement. The right amount of magnesium — and not much more — should keep our bones and muscles in tip-top shape.

How much magnesium should I take daily?

The recommended amount of magnesium that women over 50 years old should take in a day is 320 milligrams (mg) through a combination of foods, beverages, and a dietary supplement if needed. Haggans adds that no adult should ingest more than 350 mg of this mineral in supplement form each day, as this could lead to magnesium toxicity.

“Taking a supplement [with a dosage of less than 350 mg] is safe, assuming that person is healthy and isn’t getting any other supplemental magnesium from other dietary supplements or medications,” she says. “But, taking a supplement [with a higher dosage] can cause health problems.”

It’s always good to speak with your doctor before starting any supplement to avoid health complications. Staying on the safe side when taking this mineral, especially in capsule form, helps to ensure that you get the maximum benefits for your body over time!