Secret Shopper: Will magnesium help me sleep?

It seems like everyone could use more sleep—better quality slumber, too. As evidence, sales of sleep supplements skyrocketed during the pandemic and have continued climbing, raking in an estimated $1.35 billion in 2022, according to Nutrition Business Journal. While melatonin remains the most popular natural sleep aid, research-backed magnesium is gaining more traction. Our Secret Shopper hit up one natural products retailer to assess their knowledge on this mineral’s potential sleep benefits.

Natural Foods Merchandiser: Is magnesium good for sleep?

Retailer: Definitely. It’s generally very calming for both the brain and body.

Natural Foods Merchandiser: What if I already get plenty of magnesium from food? Can a magnesium supplement still help with sleep?

Retailer: It probably wouldn’t hurt to try. It’s hard to get too much magnesium from food.

Natural Foods Merchandiser: What’s the best form and dosage to take?

Retailer: I don’t know that there’s one best form, per se. Some people really like liquid magnesium supplements; others prefer pills. The dose depends on body size, and each product is different, so always follow the instructions on the label. 

How did this retailer do?

Our expert educator: Nicole Avena, Ph.D., associate professor of neuroscience at Mount Sinai School of Medicine

Overall, the sales associate gets an A for delivering great information to the public. Magnesium can be great for helping with sleep, and almost all of us don’t receive enough of it from the food we eat.

Studies using magnesium for sleep have shown it to increase sleep time, melatonin production and serum renin, which correlates to slow-wave sleep (AKA deep sleep). Studies have also reported that magnesium use is associated with decreased overall cortisol concentration. This is our fight-or-flight hormone that can contribute to insomnia when elevated for too long from things like chronic stress.

One aspect that the associate did not address was the type of magnesium used. We now know that specific types of magnesium supplements are more beneficial because they are more bioavailable and therefore better absorbed by our cells. Magnesium glycinate and magnesium malate have been studied for best absorption.

Additionally, the associate did not specify a dosage. The recommended amount of magnesium for optimal sleep is 200 to 250 mg around mealtime. Magnesium should be taken with dinner or with a snack after dinner to prevent stomach upset.