The Different Types Of Magnesium

The rundown on different types of magnesium:

• In a nutshell: Magnesium comes in a range of forms that differ in absorption and how they benefit the body.
• The different types: Common forms include magnesium citrate, oxide, sulfate, hydroxide and gluconate, along with chelated forms such as magnesium glycinate (bisglycinate).
• Why it matters: The type you choose affects muscle, nerve and bone support, as well as how well your body can use it.
• How to pick: Match the type to your needs such as muscle health, digestive systemor general wellbeing

Magnesium is a mineral found abundantly in foods such as pumpkin seeds, brown rice ,dark chocolate, and in dietary supplements1. The body needs magnesium to support muscle and nervous system health, as well as to support cardiovascular system and bone health2.

There are different types of magnesium supplements available, which contain various forms of magnesium, such as magnesium citrate, magnesium glycinate and magnesium oxide. These different forms vary in their bioavailability (the extent to which it is absorbed in the digestive tract, OR meaning more is absorbed and reaches the circulation, so it can be utilised by the body). 

So what are the different types of magnesium? Let's take a look.

What does magnesium do?

Magnesium plays a role in over 300 of the body's enzymatic biochemical reactions (chemical reactions that take place inside cells and form the basis of all the body's processes), such as those involved in supporting energy production, muscle health and function, and nerve conduction, bone health, heart health and body electrolyte balance2.

However, many people are at risk of magnesium deficiency as a result of some of the factors such as certain medications, excess consumption of ultra processed foods, and a general decline in the magnesium content of our food crops3. When dietary intake is inadequate, magnesium supplements may support general health and wellbeing.

Do different magnesium types do different things?

Generally, most supplement forms of magnesium act similarly in that they maintain magnesium levels in the body. This supports the body with a variety of activities, such as those involved in energy production, assisting in protein synthesis in the body and supporting neuromuscular function, supporting healthy muscle contraction function, and maintaining cardiovascular system and bone health4.

Importantly, not all forms of magnesium are created equal. Generally, organic forms of magnesium (containing carbon) tend to be more easily absorbed and therefore more bioavailable than inorganic forms5.

How many types of magnesium are there?

There are 5 main types of magnesium, according to the National Institutes of Health, including magnesium oxide, magnesium citrate, magnesium sulfate, magnesium hydroxide and magnesium gluconate6. 

This list reflects the most common inorganic salts, though chelated, organic forms like magnesium glycinate have also become a popular option in supplements thanks to their absorption profile5. 

What is chelated magnesium?

Chelated magnesium refers to a form of magnesium that has been bound to another compound, most commonly an amino acid, to form a stable, more absorbable complex8.

This is why chelated magnesium is generally classed as an organic form, similar to magnesium citrate. Organic forms of magnesium tend to be more easily absorbed, than inorganic forms such as magnesium oxide or magnesium sulfate5.

Common chelated forms found in magnesium supplements include magnesium glycinate (also labelled magnesium bisglycinate), where magnesium is bound to the amino acid glycine2.

Magnesium glycinate (bisglycinate)

Magnesium glycinate is a chelated, organic form of magnesium, meaning the mineral is bound to the amino acid glycine2, 8. You may also see it listed as magnesium bisglycinate on ingredient panels.

As with other organic, chelated forms of magnesium, magnesium glycinate is generally considered a well-absorbed option compared with inorganic salts5, 8.

So if you were asking “what is the difference between magnesium glycinate and magnesium bisglycinate”, the answer is that they are the same compound referred to by a slightly different name.

Magnesium glycinate benefits

Like other forms of magnesium, magnesium glycinate contributes to magnesium levels within normal range in the body, supporting the same broad range of functions shared across magnesium types - including energy production, muscle function,nerve function, and bone health4.

Because it's bound to glycine, magnesium glycinate has attracted particular interest for supporting relaxation and sleep. Glycine on its own has been shown to help improve subjective sleep quality when taken before bed13. Magnesium has also been studied in this space. In one small clinical trial, older adults with insomnia who took a magnesium supplement showed improvements in some measures of sleep quality11.

Separately, a systematic review has explored a potential link between magnesium supplements and support for feelings of stress and anxiety, although larger, higher-quality studies are still needed before firm conclusions can be drawn12.

What does that make chelated magnesium glycinate?

Magnesium glycinate is, by definition, a chelated form of magnesium – it's created by binding magnesium to the amino acid glycine8. So when a label refers to “chelated magnesium glycinate,” it's describing the same ingredient covered above. “Chelated” simply refers to the way the magnesium and glycine are bonded together, rather than pointing to a separate or different product5, 8.

Magnesium citrate

Magnesium citrate, an organic form of magnesium contains magnesium attached to citric acid. Citric acid is an organic compound that is abundant in citrus fruits.

Magnesium citrate benefits

Of all the forms of magnesium studied, magnesium citrate is more bioavailable when compared to some other forms of magnesium, and therefore offers the best bioavailability profile (meaning more is absorbed and reaches the circulation, so it can be utilised by the body)7.

Magnesium oxide

Magnesium oxide is an inorganic form of magnesium that is relatively cheap and contains a high amount of elemental magnesium8. However, magnesium oxide is not as easily absorbed as magnesium citrate9.

Magnesium oxide benefits

Like any form of magnesium, magnesium oxide maintains magnesium levels within normal range in the body10.

Which type of magnesium is best?

The best forms of magnesium are those with higher bioavailability, such as magnesium citrate and chelated forms like magnesium glycinate5. However, the exact type of magnesium that's best for you will depend on your own needs.

Magnesium to support muscle health and function

Magnesium relieves muscle cramps and helps decrease mild muscle spasms when dietary intake is inadequate. It supports muscle relaxation and healthy muscle contraction function14.

How do I choose a magnesium supplement?

When choosing the right magnesium supplement, one thing you may want to consider is the format of your supplement. Do you prefer a supplement in the form of tablets that you can easily add to your wellbeing routine? Or if you have difficulty swallowing a capsule, you may prefer a powder format. Magnesium supplements also come in as gummies and effervescents, making it easy to take your supplements on the go.

Explore more about magnesium, including a quick guide on what it's good for and foods high in magnesium on the Swisse Wellness Hub.

References:

1. Harvard School of Public Health. The Nutrition Source: Magnesium. https://www.hsph.harvard.edu/nutritionsource/magnesium/ [accessed 20/07/2023]
2. National Institutes of Health, US Department of Health and Human Services. Magnesium. https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/ [accessed 20/07/2023]
3. DiNicolantonio, J. J., O'Keefe, J. H., & Wilson, W. (2018). Subclinical magnesium deficiency: a principal driver of cardiovascular disease and a public health crisis. Open heart, 5(1), e000668. https://doi.org/10.1136/openhrt-2017-000668
4. Al Alawi, A. M., Majoni, S. W., & Falhammar, H. (2018). Magnesium and Human Health: Perspectives and Research Directions. International journal of endocrinology, 2018, 9041694. https://doi.org/10.1155/2018/9041694
5. Pardo, M. R., Garicano Vilar, E., San Mauro Martín, I., & Camina Martín, M. A. (2021). Bioavailability of magnesium food supplements: A systematic review. Nutrition (Burbank, Los Angeles County, Calif.), 89, 111294. https://doi.org/10.1016/j.nut.2021.111294
6. Allen, M.J. and Sharma, S. (2019). Magnesium. [online] Nih.gov. Available at: https://www.ncbi.nlm.nih.gov/books/NBK519036/.
7. Walker, A. F., Marakis, G., Christie, S., & Byng, M. (2003). Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study. Magnesium research, 16(3), 183-191.
8. Blancquaert, L., Vervaet, C., & Derave, W. (2019). Predicting and Testing Bioavailability of Magnesium Supplements. Nutrients, 11(7), 1663. https://doi.org/10.3390/nu11071663
9. Medscape. Magnesium Oxide (OTC). https://reference.medscape.com/drug/mag-ox-400-uro-mag-magnesium-oxide-999517#4 [accessed 21/07/2023]
10. Mori H, Tack J, Suzuki H. Magnesium Oxide in Constipation. Nutrients. 2021 Jan 28;13(2):421. doi: 10.3390/nu13020421. PMID: 33525523; PMCID: PMC7911806.
11. 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. 2012 Dec;17(12):1161-9. PMID: 23853635; PMCID: PMC3703169.
12. Boyle NB, Lawton C, Dye L. The Effects of Magnesium Supplementation on Subjective Anxiety and Stress-A Systematic Review. Nutrients. 2017 Apr 26;9(5):429. doi: 10.3390/nu9050429. PMID: 28445426; PMCID: PMC5452159.
13. Yamadera, W., Inagawa, K., Chiba, S. et al. Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes. Sleep Biol. Rhythms 5, 126-131 (2007). https://doi.org/10.1111/j.1479-8425.2007.00262.x
14. Maria Grazia Tarsitano, Quinzi, F., Folino, K., Greco, F., Francesco Pio Oranges, Cerulli, C. and Gian Pietro Emerenziani (2024). Effects of magnesium supplementation on muscle soreness in different type of physical activities: a systematic review. Journal of translational medicine, 22(1). doi:https://doi.org/10.1186/s12967-024-05434-x.