Jaw clenching, also known as bruxism, is something many people struggle with. It may be in the form of teeth grinding or simply repetitive clenching of the jaw and can lead to intense headaches, jaw pain, dental damage and facial asymmetry. It can occur anytime but it commonly occurs during sleep - an estimated 13% of the population are affected by sleep bruxism.1
Jaw clenching is due to the excess activity of the muscles controlling movement of the jaw.
The causes of this can vary but stress/anxiety, sleep disorders, and some medications have all been theorised to be potential causes.2 Another potential cause, that we will be focusing on here, is a deficiency in an essential de-stressing mineral – magnesium.3
How does magnesium affect jaw clenching?
Magnesium is implicated in the negative consequences of jaw clenching through its role in stress management and proper muscle function. It competes with calcium (another mineral required for connecting the nervous system to the muscular system) to allow muscles to fire appropriately.4 Whilst calcium generally encourages muscles to fire, magnesium can encourage muscles to relax. By modulating calcium with appropriate magnesium levels, excess and undesired muscle contractions can also be prevented.
Whilst there are many causes of jaw clenching, the improper and overactive muscle contractions of the jaw muscles may be treated by increased magnesium intake. This same phenomenon which can lead to rapid awakening in the night, can also be dealt with by providing more magnesium to compete with calcium and cool any excess stress that can lead to jaw clenching and sleep bruxism. Sufficient intake of magnesium is very important to allow the proper firing of muscles, but also to limit their overactivity in cases such as jaw clenching.
For the same reason, magnesium can also be a good option to minimise improper muscle contractions elsewhere in the body, such as those experienced in restless leg syndrome or cramps, and has even been shown to enhance athletic performance.5
Which magnesium is best for jaw clenching?
So we know that magnesium can help, but what are some good sources of magnesium?
Well firstly, a well-balanced diet should provide plenty of good sources and foods such as:
- Pumpkin seeds
- Chia seeds
Each of which provides between 43 mg and 136 mg of magnesium per serving.
For most, this will be sufficient and appropriate dietary choices are enough to prevent this magnesium deficiency-related issue from occurring. Dietary changes to consume more magnesium-rich foods may also be a good option for those who are already suffering from jaw clenching or sleep bruxism issues.
For almost all micronutrient deficiency-related issues, the ‘natural’ route of improved dietary nutrition is probably the best option, but this may not always be possible or desirable.6 For some, dietary changes to get more magnesium-rich food are too difficult or inconvenient. For this group of people, alternatives in the form of magnesium dietary supplements exist. As magnesium is ‘water-soluble’, it generally digests well and is well absorbed alongside water.7 This high level of ‘bioavailability’ means that magnesium supplements can be a good source of this essential mineral.
However, studies have shown significant differences in the bioavailability of magnesium types. The most bioavailable and thus useful form of magnesium seems to be magnesium citrate, whilst magnesium oxide seems much worse.8,9 Though evidence is somewhat lacking on every form of magnesium supplement, it is generally recommended to choose ‘organic’ forms of magnesium supplements instead of ‘inorganic’ (this has nothing to do with the same type of ‘organic’ that you may see when buying fruit or vegetables and is solely a description of the chemical composition of the mineral). Despite the higher magnesium content of inorganic magnesium forms, the great bioavailability of organic magnesium supplements means that the body will be able to access and utilise more of the magnesium from organic magnesium forms.8
For this reason, when choosing a form of magnesium supplement, be sure to check the small print to see exactly which type of magnesium you’re buying. Feel free to give the magnesium type a search on the internet to check whether it is an organic or inorganic form and whether it will improve jaw clenching significantly.
How much magnesium should I take for jaw clenching?
The European Food Safety Agency (EFSA) has provided their recommended values for adequate intake of magnesium for different age groups and whether people are assigned female at birth (PAFAB) or people are assigned male at birth (PAMAB).10
|Age range||Recommended intake of magnesium|
|18 years old and over||PAFAB - 300 mg/dayPAMAB - 350 mg/day|
|10-18 years old||PAFAB - 250 mg/dayPAMAB - 300 mg/day|
|3 - 10 years old||230 mg/day|
|1 - 3 years old||160 mg/day|
People who meet these values are likely to have no issues with magnesium deficiency disorders. However, whilst this is the recommended dosage for healthy individuals, it is also important to understand that lifestyle factors such as smoking, alcohol consumption, and diabetes can reduce the absorption of magnesium.11 Likewise, a vitamin D3 deficiency may also decrease the absorption of magnesium.12 Individuals affected by these factors may find reduced effectiveness from the EFSA-recommended magnesium intake, and could still suffer from jaw clenching or other magnesium deficiency-related issues.
Research has also shown a significant improvement in sleep quality and a reduction in stress levels for elderly adults when consuming 500mg of magnesium.13 From the improvement in two factors linked to jaw clenching at night, it is reasonable to link improved sleep and reduced stress found in this study to a reduction in sleep bruxism. However, with the knowledge that ageing has been linked to a 30% reduction in magnesium absorption, younger individuals may be able to achieve the same benefits for jaw clenching with just 70% (350 mg) of the supplementary dose of magnesium.11
Side effects and other concerns
Though rare, magnesium side effects are possible.
The most common forms of side effects are:14
- Stomach cramps
Though magnesium is typically filtered through your body and cleared via urine, magnesium toxicity can occur due to excess magnesium intake. The recommended maximal doses of magnesium before any side effects can be experienced are purely from supplemental magnesium, as dietary magnesium is filtered out well enough to be considered unproblematic at any known limit.
The recommended maximum intake of supplementary magnesium.14
|Age range||Recommended intake of supplementary magnesium|
|9 years old and over||350 mg/day|
|4 - 8 years old||110 mg/day|
|1 - 3 years old||65 mg/day|
|Below 1 years old||Not established|
Though some of the maximum daily intakes are the same as or similar to the recommended adequate values, it is important to remember that these common side effects are mild and only some people will experience these. These mild symptoms are early signs of excess magnesium toxicity, an issue which could potentially (in cases of around 5,000 mg of magnesium consumed per day) cause hypomagnesaemia and lead to symptoms such as irregular heartbeat, low blood pressure, and possibly death.15,16
Additionally, due to the other factors that affect jaw clenching or the absorption of this mineral, magnesium alone may not be sufficient to fully prevent this issue.
Magnesium deficiency is one of many factors contributing to jaw clenching and sleep bruxism. This mineral deficiency creates an imbalance where insufficient modulation by magnesium encourages muscles to fire excessively, and result in the malfunction of the nervous and muscular system. This can cause stress to build up and the jaw muscles to become overactive. Magnesium can be found in many dietary choices and is recommended due to the lack of side effects from this source. Magnesium supplements may also be a good idea but should not make up the bulk of daily magnesium intake due to the proximity of recommended daily intake and maximal daily tolerable supplemental intake. With an appropriate diet, moderate supplementary doses, and considered supplementary choices; additional magnesium intake can be a very easy and effective way to reduce stress levels and limit jaw clenching and sleep bruxism issues.
- Yap AU, Chua AP. Sleep bruxism: Current knowledge and contemporary management. J Conserv Dent [Internet]. 2016 [cited 2023 May 24];19(5):383–9. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5026093/
- Aguilera SB, Brown L, Perico VA. Aesthetic treatment of bruxism. J Clin Aesthet Dermatol [Internet]. 2017 May [cited 2023 May 24];10(5):49–55. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5479477
- Cuciureanu MD, Vink R. Magnesium and stress. In: Vink R, Nechifor M, editors. Magnesium in the Central Nervous System [Internet]. Adelaide (AU): University of Adelaide Press; 2011 [cited 2023 May 24]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK507250/
- Alkhatatbeh MJ, Hmoud ZL, Abdul-Razzak KK, Alem EM. Self-reported sleep bruxism is associated with vitamin D deficiency and low dietary calcium intake: a case-control study. BMC Oral Health [Internet]. 2021 Jan 7 [cited 2023 May 24];21(1):21. Available from: https://doi.org/10.1186/s12903-020-01349-3
- Zhang Y, Xun P, Wang R, Mao L, He K. Can magnesium enhance exercise performance? Nutrients [Internet]. 2017 Aug 28 [cited 2023 May 25];9(9):946. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5622706/
- Zhang FF, Barr SI, McNulty H, Li D, Blumberg JB. Health effects of vitamin and mineral supplements. BMJ [Internet]. 2020 Jun 29 [cited 2023 May 26];369:m2511. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7322674/
- Jahnen-Dechent W, Ketteler M. Magnesium basics. Clin Kidney J [Internet]. 2012 Feb [cited 2023 May 26];5(Suppl 1):i3–14. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4455825/
- Rylander R. Bioavailability of magnesium salts – a review. Journal of Pharmacy and Nutrition Sciences [Internet]. 2014 Jan 5 [cited 2023 May 26];4(1):57–9. Available from: https://setpublisher.com/index.php/jpans/article/view/1618
- Kappeler D, Heimbeck I, Herpich C, Naue N, Höfler J, Timmer W, et al. Higher bioavailability of magnesium citrate as compared to magnesium oxide shown by evaluation of urinary excretion and serum levels after single-dose administration in a randomized cross-over study. BMC Nutrition [Internet]. 2017 Jan 11 [cited 2023 May 26];3(1):7. Available from: https://doi.org/10.1186/s40795-016-0121-3
- EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). Scientific opinion on dietary reference values for magnesium. EFS2 [Internet]. 2015 Jul [cited 2023 May 26];13(7). Available from: https://data.europa.eu/doi/10.2903/j.efsa.2015.4186
- Schwalfenberg GK, Genuis SJ. The importance of magnesium in clinical healthcare. Scientifica (Cairo) [Internet]. 2017 [cited 2023 May 26];2017:4179326. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5637834/
- Krejs GJ, Nicar MJ, Zerwekh JE, Norman DA, Kane MG, Pak CYC. Effect of 1,25-dihydroxyvitamin D3 on calcium and magnesium absorption in the healthy human jejunum and ileum. The American Journal of Medicine [Internet]. 1983 Dec [cited 2023 Aug 23];75(6):973–6. Available from: https://linkinghub.elsevier.com/retrieve/pii/000293438390877X
- Abbasi B, Kimiagar M, Sadeghniiat K, Shirazi MM, Hedayati M, Rashidkhani B. The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial. J Res Med Sci [Internet]. 2012 Dec [cited 2023 May 26];17(12):1161–9. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3703169/
- Read ‘dietary reference intakes for calcium, phosphorus, magnesium, vitamin d, and fluoride’ at nap. Edu [Internet]. [cited 2023 May 26]. Available from: https://www.nap.edu/read/5776/chapter/1
- Kutsal E, Aydemir C, Eldes N, Demirel F, Polat R, Taspnar O, et al. Severe hypermagnesemia as a result of excessive cathartic ingestion in a child without renal failure: Pediatric Emergency Care [Internet]. 2007 Aug [cited 2023 Aug 23];23(8):570–2. Available from: http://journals.lww.com/00006565-200708000-00011
- Cascella M, Vaqar S. Hypermagnesemia. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 [cited 2023 May 26]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK549811/