The 6 Best Magnesium Supplements, According to Dietitians

YOU LIKELY KNOW that magnesium is a mineral. But what exactly does it do for you?

“Magnesium helps maintain a healthy heart rate, so you literally can’t live without it,” says Kim Yawitz, R.D., gym owner of CrossFit 26 in St. Louis, Mo. “But heartbeat aside, magnesium plays a key role in more than 300 chemical reactions in the body. It’s involved in DNA repair, protein synthesis, bone health, fluid and electrolyte balance, bone health, energy production, and muscle contraction—just to name a few.”

As Yawitz explains, because magnesium plays a role in so many important bodily functions, it’s not surprising that a low dietary intake could lead to health problems. “Studies have linked low magnesium intake with an increased risk of type 2 diabetes, high blood pressure, inflammation, heart disease, stroke, migraine headaches, asthma, and colon cancer,” she says.

Before turning to magnesium supplements, tweaking your diet to contain more magnesium-rich foods may be a good move. “The best way to get enough magnesium is to eat lots of nuts, seeds, leafy greens, whole grains, and legumes,” says Yawitz. “But if you’re among the estimated 60 percent of adults who don’t do that, a supplement can help you to cover your bases.”

Unfortunately, as Yawitz shares, it’s actually pretty difficult to diagnose magnesium deficiency. “It doesn’t always show up on a lab test, because most magnesium is stored in the bones.”

As always, consult with a healthcare professional before adding a new supplement to your routine.

Magnesium supplement benefits

With all the above being said, the active set may particularly benefit from magnesium supplements. “There’s some evidence that athletes may need more magnesium than less active adults, possibly because the body uses more magnesium during exercise,” says Yawitz. “In one small study, magnesium supplements appeared to help reduce muscle damage after a multistage bike race. Overall, though, the research is mixed on whether supplements are helpful for exercise performance.”

In healthy adults, Yawitz also points out, there’s some evidence that magnesium supplements may improve sleep and mood in those prone to insomnia and depression.“In one meta-analysis, adults taking magnesium supplements fell asleep an average of 17 minutes faster and slept 16 minutes longer per night than those taking a placebo,” she says. “And in another large study, young adults taking magnesium reported better sleep quality than those who didn’t take it.” In yet another study, Yawitz comments, adults with mild to moderate depression saw significant improvements in depression and anxiety symptoms after taking magnesium supplements for just six weeks.

Taking magnesium supplement may be useful for those with chronic disease. “One meta-analysis also suggests that magnesium supplements could help reduce the odds of type 2 diabetes, heart disease, hypertension, and other chronic illnesses by reducing systemic inflammation,” says Yawitz.

How much magnesium do you actually need every day?

Healthy adult males require about 400 to 420 milligrams (mg) of magnesium per day, says Yawitz. “Your ideal supplement dose depends on how much you’re getting through your diet,” she says, adding that an app like Cronometer can help you estimate your daily intake, so you don’t overdo it on supplements (which can cause diarrhea, nausea, vomiting, and other side effects).

“Regardless of dietary intake, I always suggest starting at a low dose of 100 to 150 milligrams (mg) per day and taking no more than 300 mg per day,” says Yawitz. “Keep in mind that certain medications—like antacids and laxatives—often contain magnesium,” she continues, stressing that you should check with your doctor or pharmacist before starting a supplement, especially if you take prescription or over-the-counter meds.

Below are six top-notch magnesium supplements selected by Yawitz and Amy Gorin, M.S., R.D.N, an inclusive plant-based dietitian and owner of Master the Media in Stamford, CT.

Which is the best form of magnesium to take?

There are several different types of magnesium supplements on the market. Kieran McSorley, R.D., of Brentwood Physiotherapy, goes by the quote that “The best form of magnesium is the one that your body absorbs best." As McSorley highlights, magnesium is available in several forms, including magnesium oxide, magnesium citrate, magnesium glycinate, and magnesium chloride. “The form of magnesium you choose may depend on the reason you are taking it, as well as any potential side effects you may experience,” he says. “Some forms of magnesium can cause digestive upset, while others are better tolerated. It's important to work with a healthcare provider to determine the best form of magnesium for your individual needs.”

Pallini Winnifred, R.D.N., of FitDominium says that the best form of magnesium is the kind that your body can absorb and use the most easily. “The bioavailability of magnesium, which refers to how well the body can absorb and use the mineral, might vary between different forms,” says Winnifred. “Many people handle some magnesium salts well, including magnesium citrate and magnesium glycinate, which are both highly accessible forms of the mineral. On the other hand, magnesium oxide is less bioavailable, but because it is cheap, it is often used as a dietary supplement.”Some nutritionists, such as Mary Sabat, M.S., R.D.N., L.D. owner of BodyDesigns, single out magnesium glycinate in particular. “It is a chelated form of magnesium that is easily absorbed by the body, making it an effective way to supplement your magnesium levels,” she says.

Side effects of magnesium deficiency

You need adequate magnesium to live. “Magnesium is important for many body functions, such as energy metabolism, protein synthesis, and nerve function,” says Winnifred.

According to Winnifred, here are just a few of the not-so-fun symptoms that may result from not getting enough magnesium: Exhaustion, muscle cramps, weakness, irritability, and trouble sleeping. “Magnesium deficiency can, in extreme situations, cause seizures, cardiac problems, and other medical complications,” she adds. As always, consult with a trusted healthcare professional if you’re concerned you’re not getting enough magnesium in your diet.

Foods highest in magnesium

For adult men, says Winnifred, it is advised to strive for a daily magnesium intake of 400 to 420 mg. To get your fix, she recommends dark, leafy greens like spinach (1 cup has 157 mg of magnesium), almonds (1 oz contains 80 mg of magnesium), and black beans (1 cup contains 120 mg of magnesium). Salmon, avocados, and bananas are also excellent suppliers of magnesium,” she adds.

Sabat also calls out the dark leafy green Swiss chard and pumpkin seeds for their impressive nutrition specs, particularly when it comes to magnesium. “A one cup serving of cooked Swiss chard contains 150mg, and a one ounce serving of pumpkin seeds contains 150mg,” she says, noting that spinach and Swiss chard are both excellent sources of vitamin A and vitamin C, while pumpkin seeds are also a good source of fiber and protein.

If you do need a supplement, here are a few recommended by dietitians.