Does Magnesium Help with Sleep?

Does Magnesium Help with Sleep?

CrossFit Sleep Supplements

Different vitamins, minerals, and supplements trend each year in the world of health and wellness.

Vitamin D is really getting it's time in the sun right now. With the hyper focus on viruses and our immune system, several studies have now shown that having adequate vitamin D levels are strongly correlated to lower chances of getting Covid-19,  less intense infections, and less chance of dying if you do get Covid. It's important. You should get some. You gotta take that shit.

But you should also know that to properly metabolize and use Vitamin D, you need to have enough of its less trendy friend Magnesium.

Magnesium is one of the most important nutrients because it helps you to properly use other nutrients, like vitamin D. It is also part of the critical path for making energy in your cells. 

In addition to vitamin D metabolism and energy to fuel your cells, magnesium also plays an important role in:

  • Making the brain chemical GABA - which makes you feel calm and initiates sleep.
  • Stress reduction and stabilizing your moods.
  • Regulating your heart beat.
  • Bone and muscle formation.
  • Maintaining hydration and fluid balance (it's an important electrolyte).
  • Nerve transmission and muscle contractions .
  • 300+ different enzyme reactions.

It's kind of a big deal. And, magnesium is an essential nutrient, which means you can't make it. You have to get it in your diet. Most people are not good at getting enough of it, since it is mostly found in leafy greens, seeds, beans, and nuts.  Even if you have a healthy diet, you burn through a lot of magnesium when you workout and sweat, and when you are stressed or sick.  Also, there are many people who argue that our soil is depleted of magnesium, so even our food sources are lacking. Some studies suggest that 75% of Americans do not meet their dietary requirements for magnesium. 

When you are low, your body pulls magnesium from your bones to be used elsewhere. Over time, this can decrease bone density and put you at risk for osteoporosis. People almost never show low levels of magnesium on a blood tests, because the body will use stored magnesium to keep blood levels normal. So it is hard to detect deficiencies without invasive procedures.  A 2018 article published in the British Medical Journal's 'Open heart'  journal warns: "the literature suggests that subclinical magnesium deficiency is rampant and one of the leading causes of chronic diseases including cardiovascular disease and early mortality around the globe, and should be considered a public health crisis.(1)" Yikes.

Signs of low magnesium include:

  • fatigue
  • muscles weakness
  • muscles twitches and cramps
  • irregular heart beat
  • depression
  • anxiety
  • restless sleep and waking frequently during the night

Given these effects, it is easy to see how bumping up your magnesium intake could help your brain and body to relax, wind down, and sleep better.

What happens when people use magnesium for sleep?

In one study, older adults were given either 500 mg of magnesium or a placebo. In the group that took magnesium they found a significant increase in total amount of sleep, less waking up in the night, and less time taken to fall asleep.  The magnesium takers also had higher levels of renin and melatonin, two hormones that help regulate sleep (6).

Another study had adults take magnesium for 20 days and then had them undergo a clinical sleep study where they measured their brain activity and also took blood samples to measure changes in hormones. This study found that after taking magnesium there was a significant increase in slow-wave sleep (deep sleep) and stronger delta waves, which is a measure of the quality of deep sleep. There was also in increase in sigma powder, which is an indication of the sleep spindles that happen in the brain when you are consolidating memories and having good communication between different brain regions during sleep.  This study also found a decrease in cortisol levels.

Taken together, these are all signs of improved sleep quantity and quality and less stress after taking magnesium supplements.

Magnesium is also great for relaxing.

A recent study, published in February 2021, had subjects randomly assigned to take either magnesium or a placebo pill for 24 weeks. They then took measurements of cortisol, the stress hormone, over a 24 hour period. They found the magnesium group had signifcantly lower cortisol levels and an increase in a compound called 11β‐HSD type 2, which keeps the body from over activating cortisol production (4).

Another study, that was a big review paper looking at 18 pieces of research studying the affects of magnesium supplements on stress and anxiety found that magnesium has a beneficial effect on anxiety and that more research should be done in this area (5).

How to take Magnesium

There are a lot of different types of magnesium. The ones that are best absorbed and used by the body are ones that are attached to an amino acid, also called chelated magnesium. 

Common forms are magnesium citrate, magnesium glycinate, magnesium malate, and magnesium gluconate.

Magnesium chloride is a salt form that is often used in bath salts and can be absorbed through the skin. It is great for soaking in to relax sore and tight muscles. When used as an oral supplement it can lead to loose stools and diarrhea.

Magnesium oxide actually contains more magnesium than other types, but it is also used as a laxative because it can cause loose stools and diarrhoea.

We recommend using a magnesium chelate in the range of 200 - 400 mg per day.  This type is the best used by your body and less likely to cause digestive issues.

For sleep and night time relaxation: Take 250mg of magnesium 30 - 60 minutes before bed.  For a complete solution to support deep rest and recovery, check out our Thirdzy PM Recovery Collagen - which contains 250mg of magnesium and other all natural ingredients.

Sleep tight,
Dr. J


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*** The views expressed in this article are those of one expert. They are the opinions of the expert and do not necessarily represent the complete picture of the topic at hand. This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. 


  1. DiNicolantonio, James J et al. “Subclinical magnesium deficiency: a principal driver of cardiovascular disease and a public health crisis.” Open heart vol. 5,1 e000668. 13 Jan. 2018, doi:10.1136/openhrt-2017-000668
  2. Cao, Yingting et al. “Magnesium Intake and Sleep Disorder Symptoms: Findings from the Jiangsu Nutrition Study of Chinese Adults at Five-Year Follow-Up.” Nutrients vol. 10,10 1354. 21 Sep. 2018, doi:10.3390/nu10101354
  3. Abbasi, Behnood et al. “The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial.” Journal of research in medical sciences : the official journal of Isfahan University of Medical Sciences vol. 17,12 (2012): 1161-9.
  4. Schutten, Joëlle C et al. “Long-term magnesium supplementation improves glucocorticoid metabolism: A post-hoc analysis of an intervention trial.” Clinical endocrinology vol. 94,2 (2021): 150-157. doi:10.1111/cen.14350
  5. Boyle, Neil Bernard et al. “The Effects of Magnesium Supplementation on Subjective Anxiety and Stress-A Systematic Review.” Nutrients vol. 9,5 429. 26 Apr. 2017, doi:10.3390/nu9050429
  6. Abbasi, Behnood et al. “The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial.” Journal of research in medical sciences : the official journal of Isfahan University of Medical Sciences vol. 17,12 (2012): 1161-9.

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