First, a recap on why someone might want to take a magnesium supplement in the first place: Magnesium is a really important mineral. If you’re an avid mindbodygreen reader, you’ve probably heard us wax poetic about it before: It facilitates hundreds of chemical reactions in the body, helping to regulate blood sugar, blood pressure, muscle and nerve function, protein building, and more, registered dietitian and spokesperson for the Academy of Nutrition and Dietetics Amy Kimberlain, RDN, CDCES, explains. “Additionally,” she says, “magnesium plays a vital role in helping maintain a healthy heart and healthy bones.”
When we eat whole foods that contain magnesium (plants need the mineral to grow, too, so leafy greens tend to be high in it), about half of it is stored in bones, and the rest goes to other body tissues or is excreted by the kidneys. In addition to greens, beans, nuts, seeds, and whole grains are also good food sources of magnesium. Kimberlain explains that if a food is high in dietary fiber, chances are it contains magnesium, too.
Even though a number of healthy foods are high in magnesium, the National Institutes of Health estimates that nearly half of Americans don’t get enough of it through diet alone. On an episode of the mbg podcast, immunologist Heather Moday, M.D., said that it’s one of the most common deficiencies she sees, up there with vitamin B and zinc.
This is likely due in part to the rise in processed, nutrient-poor food. But even for those who eat a mostly unprocessed diet, industrial farming practices are increasingly stripping soil—and in turn, crops—of essential nutrients like magnesium. Magnesium levels also tend to decline with age, and there are racial and gender disparities in uptake as well.
Taking a magnesium supplement is a way to make sure your body has enough of the mineral to protect against conditions like heart disease, high blood pressure, type 2 diabetes, and other blood sugar diseases, etc.