Does Magnesium Before Bed Improve Your Sleep?

We explore the effects taking magnesium at night has on WHOOP members’ sleep and recovery.

Magnesium is frequently utilized as a sleep supplement, but does it actually increase the duration or quality of your sleep? We examine how it impacts sleep and recovery data tracked by WHOOP, plus break down the basics of what magnesium is, how it works, how much to take, and possible side effects.  

What is Magnesium?

Magnesium is a very common mineral that is essential for human health. It is something that all your cells and organs need, contributing to muscle, nerve, heart, and brain function, as well as building strong bones and regulating blood pressure and immune system activity. Many foods contain magnesium, and it is also readily available as a supplement. A popular use of magnesium supplements is to improve your sleep.  

How Can Taking Magnesium at Night Help You Sleep?

Magnesium deficiencies have often been connected to sleep disorders and poor sleep, so if you’re not getting enough of it in your diet a magnesium supplement may aid your sleep. Additionally, magnesium can help your body relax. It works to inhibit the sympathetic (fight or flight) branch of your autonomic nervous system and promote parasympathetic (rest and digest) activity instead. Magnesium is also used as a treatment for restless leg syndrome, a condition that disrupts sleep for many people.  

Benefits of Magnesium for WHOOP Members’ Sleep & Recovery

In an effort to quantify any potential sleep benefits of magnesium, we examined the data from WHOOP members when they report taking it. We learned that many of them see clear improvements in their sleep and recovery following magnesium supplements prior to bedtime. WHOOP members average 15 more minutes of sleep per night when they use magnesium, as well as 2% more REM sleep. They also wake up the next morning with an average recovery 8% higher.

WHOOP MEMBERS Average more sleep and higher recovery after taking magnesium.

We took possible confounding factors into account during this analysis to control for other sleep-promoting behaviors (like meditation before bed or a sound machine when sleeping) that you might also engage in while taking magnesium. In general, we found a greater increase in average sleep time for men (+16 minutes) as opposed to women (+ 9 minutes), and also diminishing benefits around age 40. WHOOP members between 40 and 60 years old saw no improvement in average time asleep.  

Magnesium Dosage, Risks & Potential Side Effects

Recommendations for the proper dosage of magnesium to take before bed vary, and they are often slightly higher for men than women. For the most part, something in the range of 200-350 milligrams is the suggested amount. Taking too much magnesium can cause the following:

• Cramping
• Nausea
• Diarrhea (with magnesium oxide in particular)
• Irregular heartbeat (from very high intakes)

Magnesium supplements may also interfere with certain medications. Additionally, putting more magnesium into your body than it needs can lead to magnesium toxicity, with possible symptoms including low blood pressure, muscle weakness, and vomiting.  

Magnesium for Sleep vs Melatonin

Magnesium and melatonin are often part of the same conversation when it comes to sleep aids, but they are two very different things. While magnesium is a mineral that assists numerous processes in your body, melatonin is a hormone which contributes to regulating your sleep and circadian rhythm. Generally speaking, magnesium helps your body relax and melatonin supports falling asleep faster. Many experts advise trying melatonin first before experimenting with magnesium. Some people may choose to use both simultaneously, especially to combat insomnia. READ MORE: How Much Does Melatonin Help You Sleep?  

Track How Magnesium Affects Your Sleep with WHOOP

WHOOP has a journal feature that lets you log when you take magnesium prior to sleep, as well as the dosage (and also many other choices and behaviors that can benefit or hurt your sleep). Alongside state-of-the-art sleep tracking, WHOOP uses this data to offer you actionable insights as to which behaviors improve or detract from your sleep and next-day recovery. RELATED: How Eating Before Bed Affects Your Sleep and Recovery