When You Take Too Much Magnesium, This Is What Happens To Your Heart – Health Digest

Many people take magnesium for everything from better sleep to improved workout recovery – and for good reason. This essential mineral plays a role in over 300 biochemical reactions in your body, supporting muscle and nerve function, heart rhythm, bone health, and more. You’ll find magnesium naturally in foods like pumpkin seeds, black beans, bananas, spinach, and whole wheat bread. Most women need around 310 to 320 milligrams a day, while men need closer to 400 to 420 milligrams.

Although you can reach your recommended magnesium intake with a healthy diet, the National Institutes of Health says about half of Americans fall short. A multivitamin or other magnesium supplement can help you get enough.

But don’t go overboard with magnesium supplements. Although they may slightly reduce your blood pressure, too much magnesium can cause your blood pressure to drop dangerously low. Magnesium toxicity may also result in an irregular heartbeat or even death.

Magnesium is an essential electrolyte that helps regulate your body’s electrical activity, including the rhythm of your heartbeat. Both too little and too much magnesium can disrupt that rhythm, leading to an arrhythmia (irregular heartbeat). In some cases, the lower chambers of the heart can start fluttering instead of pumping properly. When that happens, the heart can’t push blood out effectively, which can cause a rapid drop in blood pressure. The person may suddenly collapse, stop breathing, and, if not treated immediately, the heart can stop altogether.

It’s nearly impossible to get too much magnesium from food alone because your kidneys simply filter out the excess. Supplements are far more concentrated, which is why the U.S. Food and Nutrition Board set an upper limit of 350 milligrams a day for magnesium from supplements. While a multivitamin may contain around 100 milligrams, magnesium-specific supplements can add another 250 milligrams or more. Antacids and laxatives can also contain up to 500 milligrams of magnesium per dose.

In most people, taking too much magnesium leads to side effects like nausea or diarrhea. Older adults may be more vulnerable to magnesium buildup, especially if they regularly use antacids or laxatives. A 2008 study in Rejuvenation Research found that older adults with congestive heart failure and high magnesium levels lived about five months less than those with normal magnesium levels. They were also more frail, had poorer kidney function, and faced a higher risk of dying from heart failure.

People with kidney problems may be at risk for high magnesium levels in their blood because their bodies can’t properly get rid of excess magnesium. Magnesium can also interact with many types of medications. For example, people taking bisphosphonates or antibiotics may need to wait two hours before taking a magnesium supplement, as magnesium can reduce how much of the drug is absorbed by the body. Potassium-sparing diuretics may also limit the body’s ability to eliminate excess magnesium.

Although nearly half of Americans don’t get enough magnesium through their diets, adolescents and older men are especially at risk. Older adults may have a harder time maintaining healthy magnesium levels because they tend to lose more magnesium through their urine. People with alcohol use disorder may also have low magnesium levels due to kidney problems, low phosphate or vitamin D levels, or frequent diarrhea. Those with type 2 diabetes or gastrointestinal disorders may also be at risk for magnesium deficiency.

If you’re generally healthy, your body can usually manage occasional low magnesium intake by reducing how much magnesium is sent out through your urine. However, chronically low magnesium levels can lead to symptoms such as numbness, muscle cramps, or personality changes.