3 Simple Truths About Magnesium

Vanessa Raymond Fact Checked
Raw spinach on cutting board
© Jeff Wasserman / Stocksy United

Magnesium is the mineral darling of the moment. People are not only taking magnesium by tablet, capsule and powder, but also soaking in magnesium salt baths and rubbing magnesium oil into their skin. 

Magnesium gets credit for everything from preventing depression to keeping bones dense and strong and even curing migraines.

And much of the hype may be true. After all, your body uses magnesium for more than 300 biochemical reactions on the daily. Cholesterol production? Check. Electrolyte balance? Check. Blood glucose control? Check. Magnesium’s list of job duties goes on and on.

With all the press magnesium is getting, there are still a few facts about this hard-working mineral that may surprise you. Clinical dietitian Judy Simon, M.S., R.D., who practices at University of Washington Medical Center–Roosevelt, shares some little-known facts about magnesium.

You can get all the magnesium you need from a healthy diet

While the supplement industry would have you believe otherwise — magnesium is a booming business, after all — you can get enough magnesium from your diet alone by eating well.

We’ve all heard by now that we should stay away from processed foods. Instead, your diet should include lots of veggies, and the grains and fats you eat should be the healthy kind, too.

“That’s a good way to stay healthy and feel great and also a great way to get enough magnesium in your diet,” says Simon.

That’s because processed foods, refined flours and sugars lack magnesium. But magnesium hangs out in high concentrations in whole grains, leafy greens, nuts and seeds and in lesser concentrations in lots of other foods, too.

The National Institutes of Health (NIH) has put together a handy list of good sources of magnesium and it contains some pleasant surprises; both dark chocolate and nuts are good sources.

The recommended dietary allowance for women ages 31 to 50 is 320 milligrams. And if you’re pregnant, you need even a little bit more.

Your trendy diet could put you at risk of magnesium deficiency

“When whole food groups are eliminated, like they are in some diets, my alarm bells go off a little bit,” says Simon.

Take a diet like the keto diet that works by restricting carbohydrates enough to put your body into ketosis, a metabolic state of burning fat instead of carbohydrates for fuel.

“If you are trying to keep your carbs low and cut out beans and whole grains to do so, you just lost two very good sources of magnesium,” says Simon.

That extreme really isn’t necessary.

“If you focus on getting good nutrition from all the different food groups, you’ll get a little bit here and there and should easily be able to meet your magnesium needs,” says Simon.

It’s also a good idea to not overdo your alcohol and caffeine consumption, because they increase the amount of magnesium your body excretes.

It’s better to get your magnesium from food than a supplement 

Magnesium supplements can have interactions with antibiotics and some osteoporosis medications. And high doses of magnesium from supplements can cause diarrhea, nausea and abdominal cramping.

Not everyone realizes that both laxatives and antacids contain magnesium; if you use these regularly, you may be getting more magnesium than you realize. Talk with your doctor about whether you might be getting too much if that’s the case.

The NIH advises people to get most of their nutrients from food instead of supplements, and Simon and many other dietitians agree.

“When you get your magnesium through real food, you can’t get too much, and you’ll be getting all the other health benefits of eating well,” says Simon. “The great news is that the foods rich in magnesium are rich in other nutrients, too.”