Magnesium supplements are more popular than ever, and a particular focus is on helping you sleep. Nutritionist Rob Hobson looks at the evidence.
🕒 6 min read
Sleep is one of the pillars of health, yet many people struggle to achieve enough rest. Chronic sleep issues affect overall wellbeing, leading to problems like low mood, weakened immunity, and even serious health conditions like heart disease.
Although various factors contribute to sleep disturbances, one area gaining significant attention is magnesium's role in improving sleep.
Magnesium's role mainly involves its ability to regulate neurotransmitters that promote relaxation. One of its key effects is on gamma-aminobutyric acid (GABA) – a neurotransmitter that helps calm nerve activity.
Low GABA levels are associated with poor sleep, anxiety, and stress. Magnesium helps bind to GABA receptors, enhancing its calming effects and promoting relaxation, which in theory may help to improve sleep.
Does magnesium help with sleep?
Research has shown that magnesium supplements may help to improve sleep, especially for older adults. A review of several studies found that, although it didn't affect total sleep time, magnesium reduced the time it took to fall asleep by about 17 minutes.
In another study with 46 elderly participants, magnesium not only increased sleep time and efficiency but also raised melatonin levels (the hormone that regulates sleep) while reducing cortisol (the stress hormone), helping people fall asleep faster and sleep more soundly.
Magnesium can also help with sleep by affecting certain hormones and brain functions. It has been shown to promote deeper sleep by increasing slow-wave (deep) sleep and lowering cortisol levels, which tend to rise with age and disrupt sleep.
Additionally, it boosts renin and aldosterone: hormones that are important for regulating sleep patterns, suggesting that magnesium may help counteract age-related changes in these areas.
Long-term studies also show that getting enough magnesium through diet can reduce the risk of sleep disorders. Research from the Jiangsu Nutrition Study found that women who consumed more magnesium were less likely to fall asleep during the day.
Similarly, the CARDIA study showed that higher magnesium intake was associated with better sleep quality and reduced the risk of sleeping less than seven hours a night.
Magnesium supplementation has been shown to help with sleep quality in older adults, improving various measures of sleep and life quality without causing significant side-effects. This makes it a safe and affordable option for those struggling with insomnia, but further high-quality research is needed to establish definitive recommendations.
There are several different types of magnesium, and some are better at promoting sleep than others, as well as being better absorbed in the body.
What kind of magnesium should I take?
Magnesium supplements are available in various forms, including magnesium powder and tablets. Supplements may contain a single magnesium type or a combination of types. While research is mixed, and in some cases the specific type of magnesium used is unclear, there is promising evidence supporting the benefits of magnesium glycinate, citrate, malate and oxide.
Magnesium Glycinate
Magnesium glycinate is magnesium bound to glycine, an amino acid known for its calming properties. Glycine may enhance the overall calming effect of magnesium, promoting relaxation and improved sleep quality. Glycine has been shown to lower core body temperature, which is conducive to better sleep initiation and maintenance. This form is also very easily absorbed.
Mechanism
Magnesium helps activate GABA receptors in the brain, which reduce neural activity, calming the nervous system. The combined action of glycine and magnesium enhances this effect, potentially improving relaxation to help aid sleep.
Research
There are few studies looking at magnesium glycinate specifically. One study on glycinate alone showed that it helped to improve sleep by cooling the body through increased blood flow to the skin.
It does this by affecting specific brain receptors in the suprachiasmatic nucleus (SCN), which controls sleep. The lowered body temperature and faster sleep onset were linked to these receptors, but the exact mechanisms are still not fully understood.
Best For
Individuals with anxiety-related sleep disturbances, as both magnesium and glycine promote relaxation. Very absorbable, so may be gentler on the stomach than other magnesium types.
Magnesium Citrate
Magnesium citrate is commonly used for digestive issues, but it can indirectly aid sleep by alleviating discomfort caused by constipation or indigestion. Some research has shown that it may be beneficial for sleep.
Mechanism
Magnesium citrate may help by relaxing the intestinal muscles, promoting bowel movements, and alleviating discomfort that can interfere with restful sleep. It also has general magnesium benefits in terms of GABA activation and calming the nervous system.
Research
One study noted that individuals with poor baseline sleep quality who took magnesium citrate experienced improvements in sleep. Randomised control trials (RCT) evidence may support using oral magnesium citrate supplements (less than 1 g per dose up to three times a day) for insomnia symptoms.
Best For
Overall sleep improvements and those with digestive issues that affect sleep.
Magnesium Malate
Magnesium malate is bound to malic acid, an element involved in energy production, which can make it more stimulating compared to other forms. It's often recommended for daytime use due to its energising properties, but may also be beneficial for individuals suffering from fatigue-related sleep issues or conditions like fibromyalgia.
Mechanism
Malic acid plays a role in the production of ATP (energy), so while magnesium malate isn't a direct sleep aid, it may help relieve symptoms of chronic fatigue, which can indirectly lead to better sleep.
Research
Some studies suggest that improving energy metabolism during the day can help regulate the circadian rhythm and reduce symptoms of sleep disruptions related to fatigue.
Best For
Daytime use or individuals with fibromyalgia or fatigue-related sleep disturbances.
Magnesium Oxide
Magnesium oxide is one of the less bioavailable forms of magnesium, meaning it is not absorbed as efficiently by the body. It's often used as a laxative due to its ability to pull water into the intestines, promoting bowel movements.
Although it may help individuals with constipation and has all the other benefits of magnesium for energy, muscles, bones and teeth, it is less effective for those seeking sleep-specific benefits.
Mechanism
When it comes to sleep, magnesium oxide primarily works by drawing water into the colon, which can relieve constipation and digestive discomfort that might disrupt rest.
Research
Some studies showing improvements in sleep have used magnesium oxide, but this has been in large quantities (more than 800 mg). Given the lower absorption of this type of magnesium compared to other types, it is unlikely to be the best choice for sleep.
Best For
Individuals dealing with constipation, but may not be ideal for those looking to improve sleep directly given the high doses required.
Healthspan Opti-Magnesium
Opti-Magnesium's formulation includes magnesium citrate, which has been shown in research to improve sleep, as well as magnesium malate – both highly absorbable magnesium forms.
Opti-Magnesium
Highly absorbable 375mg magnesium per dose
- Benefits to bones, teeth, muscles, psychological function, energy levels and nervous system
- Best magnesium formulation with highly absorbable magnesium citrate and malate
- Daily dose of two tablets provides 375mg magnesium
If you're considering supplementation to help with sleep, you should take them in moderation as part of a broader sleep hygiene routine.
It's also important to tailor magnesium supplementation to your specific needs, considering factors such as digestive tolerance and the main benefits you're aiming for.