Magnesium & Muscles

Magnesium & Sleep: How it Works & When to Take it

a woman sleeping deeply while smiling to herself
If you’re like almost half the Australian population1, you’ll be familiar with the feeling of your mind racing and body tossing and turning when you just want to be asleep. Could magnesium be the missing link in your nightly routine?


How magnesium may help with the nightly routine

Magnesium performs hundreds of important tasks in the body; among these it helps you maintain normal nervous system function and supports a healthy response to stress.  If you’re finding it hard to sleep because you’re feeling stressed or stuck in a late-night thought spiral, magnesium may be helpful. Magnesium plays an essential role in putting the brakes on your stress response. It helps regulate stress hormones and modulates the activity of the calming neurotransmitter, GABA.2 Interestingly, ongoing stress can also deplete the body of magnesium.2 So if stress reduces magnesium levels but magnesium is needed to dampen the stress response, it can create a vicious stress cycle.2 When stress arises, we can often feel restless. Magnesium can also be helpful here as it plays a key role in muscle relaxation.

Furthermore, magnesium is involved in the pathway for melatonin,3 which controls the body’s sleep and wake cycles (circadian rhythm).

A recent Australian study found a relationship between low magnesium levels and poor-quality sleep in healthy mature adults.3 Researchers observed that magnesium levels were significantly lower in those who reported getting fewer than 7 hours sleep a night.


How much magnesium should you have before bed?

To calm a racing mind and relax your body’s muscles, magnesium is particularly powerful when combined with a calming herb like passionflower (Passiflora incarnata). Passionflower is traditionally used in Western herbal medicine to calm the mind and relieve restless sleep. It is believed to work by increasing levels of GABA in the brain, which helps you feel more relaxed.4  To help you prepare for sleep, calm your mind and relax your muscles, you should take 300mg of easily absorbed magnesium in combination with passionflower extract for optimal results. Ethical Nutrients Mega Magnesium Night contains high strength, easily absorbed Meta Mag® (magnesium diglycinate) in combination with passionflower and the amino acid glycine to prepare you for a good night’s sleep and help promote healthy sleeping patterns. Mega Magnesium Night is available in delicious mango/passion powders and convenient tablets, and can serve as a beneficial addition to your nightly wind down routine. 


How long does it take to work?

How long supplements take to work is highly individual and depends on a number of factors like how deficient you are in the nutrient, your unique biochemistry and metabolism and if you have any health conditions that could affect their absorption in the body. On average, magnesium absorption starts approximately one hour after oral intake.5 As a general rule, you should take Mega Magnesium Night approximately one hour before you intend to go to bed to help with restlessness, sleeplessness and support a healthy stress response. It may take a number of weeks of regular use, as part of your nightly wind-down routine, to support healthy sleeping patterns. It’s important to note that natural sleeping aids are not a quick fix and you should couple supplements with healthy sleep behaviours like limiting exposure to blue light from electronic devices at least an hour before bedtime, creating a sacred sleep space that’s dark and quiet, ensuring you’re moving your body during the day and reducing caffeine intake after lunchtime.



  1. Reynolds A et al, 2019, Chronic insomnia disorder in Australia, Sleep Health Foundation, viewed 14 June 2023, <">
  2. Pickering G et al, 2020, ‘Magnesium Status and Stress: The Vicious Circle Concept Revisited’, Nutrients, vol 12, no 12, p3672
  3. Dhillon V, 2023, ‘Low Magnesium in Conjunction with High Homocysteine and Less Sleep Accelerates Telomere Attrition in Healthy Elderly Australian’, Int J Mol Sci, vol 24, no 2, p 982
  4. Guerrero F A, 2017, ‘Effect of a medicinal plant (Passiflora incarnataL) on sleep’, Sleep Science, vol 10, no 3, pp 96-100
  5. Schuchardt JP, 2017, ‘Intestinal Absorption and Factors Influencing Bioavailability of Magnesium-An Update’, Curr Nutr Sci, vol 13, no 4, pp 260-278

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