Magnesium is an essential mineral involved in over 300 biochemical reactions in the body1, supporting everything from muscle function to energy production. As awareness grows around magnesium’s benefits, many people turn to supplementation to ensure they’re meeting their daily intake requirements.
Among the most popular forms of magnesium supplements are magnesium glycinate and magnesium citrate—each offering unique benefits depending on individual needs.
In this article, we’ll break down the differences between magnesium glycinate and citrate, comparing their key benefits to help you choose which form of magnesium is best suited for your health goals.
What is Magnesium Glycinate?
Magnesium glycinate, also known as magnesium bisglycinate, is one of the most popular and widely recommended forms of magnesium, particularly for those seeking a gentle yet highly absorbable option. It combines magnesium with glycine, a beneficial non-essential amino acid.
Glycine itself plays several important roles in the body, including aiding in the production of glutathione, a powerful antioxidant, and acting as a neurotransmitter2. It is also commonly used as a sleep aid, with studies suggesting it may reduce the time to fall asleep and improve restfulness upon waking3. Glycine has also been linked to reduced daytime sleepiness and enhanced cognitive function, potentially leaving you feeling more refreshed and alert4.
Overall, magnesium glycinate is known for its superior bioavailability and its gentle effect on the digestive system, making it less likely to cause gastrointestinal discomfort compared to less absorbable forms5, like magnesium oxide. With the added potential benefits of supporting sleep quality, it’s an excellent choice for those seeking a highly absorbable form of magnesium with possible calming and relaxation effects.
Key Benefits:
- High Absorption – Magnesium glycinate is known for its superior absorption rate, which may ensure your body efficiently absorbs magnesium for maximum benefits.
- Gentle on the Stomach – This form of magnesium is less likely to cause digestive issues, such as diarrhea, often associated with cheaper, less absorbable magnesium types.
- May Promote Relaxation and Sleep – The synergistic benefits of magnesium and glycine make it a popular choice for those seeking natural support for relaxation and sleep.
What is Magnesium Citrate?
Magnesium citrate is another popular and widely-used forms of magnesium due to its high absorption rate and versatility. It combines magnesium with citric acid, the compound that gives citrus fruits their tangy flavour. This formulation helps improve the solubility of magnesium, making it easier for the body to absorb compared to some other forms.
One of magnesium’s key roles is supporting energy production, and citric acid also plays a role in energy metabolism as part of the Krebs cycle6. Interestingly, studies have shown that citric acid may reduce physical stress and fatigue7 more effectively than L-carnitine, a well-known energy supplement.
Although magnesium citrate is sometimes criticised for causing diarrhoea, this is mainly due to the availability of liquid magnesium citrate products in the U.S. that are specifically formulated and sold as laxatives. These products deliver a high dose of 1,885 mg to 2,900 mg of magnesium—well above the recommended daily intake—inducing a laxative effect by drawing water into the intestines8.
However, when taken at standard doses—such as 270 mg to 300 mg, as advised by the UK health authorities9—magnesium citrate offers excellent benefits without the harsh side effects. Overall It’s a great all-round magnesium supplement for supporting the general benefits of magnesium10, including energy production, muscle, nerve and psychological function.
Key Benefits:
- Highly Absorbable: Magnesium citrate is known for its high absorption rate, making it an effective way to boost magnesium levels in the body. The combination with citric acid enhances magnesium’s solubility, allowing for better uptake by the digestive system.
- Supports Energy Production: Both magnesium and citric acid play key roles in the body’s energy production, helping to reduce tiredness and fatigue. This makes magnesium citrate an excellent choice for those looking to naturally boost their energy levels.
- Everyday General Use: Magnesium citrate is a popular choice for those seeking an all-round magnesium supplement to support the body’s daily magnesium needs.
Magnesium Glycinate vs Citrate – Key Differences
When choosing between magnesium glycinate and magnesium citrate, it’s essential to consider your individual health goals and how each form of magnesium works in the body. Below is a side-by-side comparison of the key features and benefits of these two popular forms of magnesium:
| Magnesium Glycinate | Magnesium Citrate | |
|---|---|---|
| Compound | Magnesium + glycine (a beneficial non-essential amino acid) | Magnesium + citric acid (the compound that gives citrus fruits their tangy flavour) |
| Elemental Magnesium % | 10-14% | 14-16% |
| Bioavailability | High | High |
| Popularity (UK Searches/Month) | 81,000 | 23,000 |
| Best For | General Supplementation, Muscles, Relaxation, Sleep | General Supplementation, Muscles, Energy |
- Elemental Magnesium % – This refers to the percentage of magnesium within each compound. A higher percentage doesn’t mean a better supplement. What matters is how much your body actually absorbs (bioavailability) and whether it delivers the desired effects.
- Popularity (UK Searches/Month) – These figures represent the number of UK Google searches per month for each type of magnesium, based on data from Semrush. This provides insight into which forms of magnesium are most commonly sought after by consumers.
Which is Better: Magnesium Glycinate or Citrate?
The answer to this question largely depends on your personal health goals and how your body responds to each form of magnesium. If you’re looking for general magnesium supplementation, both magnesium glycinate and magnesium citrate are great options, and it may simply come down to testing which one works best for your individual needs.
For sleep and relaxation, magnesium glycinate is often the go-to recommendation. This is due to the added benefits of glycine, which is commonly taken on its own as a natural sleep aid. Many people find that magnesium glycinate helps them unwind and promotes better sleep quality, thanks to glycine’s calming properties.
At MAGSUPPS, we specialise in magnesium supplements for the UK market and have combined magnesium glycinate and citrate alongside malate in our highly-rated triple magnesium complex. This all-in-one supplement offers the best of both worlds for those seeking overall magnesium support—whether it’s for muscle function, energy, or relaxation.
Ultimately, the above recommendations serve as general guidance, and it’s important to remember that individual responses to supplements can vary. What works well for one person may not have the same effect on another, so experimenting with different types of magnesium is often the best way to find what suits your body and meets your health goals best.
References:
- 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 PMCID: PMC5926493 ↩︎
- Meerza Abdul Razak, Pathan Shajahan Begum, Buddolla Viswanath, and Senthilkumar Rajagopal, “Multifarious Beneficial Effect of Nonessential Amino Acid, Glycine: A Review,” Oxidative Medicine and Cellular Longevity, vol. 2017, Article ID 1716701, 2017, https://doi.org/10.1155/2017/1716701 PMCID: PMC5350494 ↩︎
- Yamadera, W., Inagawa, K., Chiba, S., Bannai, M., Takahashi, M., & Nakayama, K. (2007). Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes. Sleep and Biological Rhythms, 5, 126–131. https://doi.org/10.1111/j.1479-8425.2007.00262.x ↩︎
- Inagawa, K., Hiraoka, T., Kohda, T., Yamadera, W., & Takahashi, M. (2006). Subjective effects of glycine ingestion before bedtime on sleep quality. Sleep and Biological Rhythms, 4, 75–77. https://doi.org/10.1111/j.1479-8425.2006.00193.x ↩︎
- Schuette, S.A., Lashner, B.A., & Janghorbani, M., “Bioavailability of Magnesium Diglycinate vs Magnesium Oxide in Patients with Ileal Resection,” JPEN Journal of Parenteral and Enteral Nutrition, vol. 18, no. 5, pp. 430-435, 1994, https://doi.org/10.1177/0148607194018005430 PMID: 7815675 ↩︎
- Khan Academy. Unit 10, Lesson 4: Pyruvate Oxidation and the Citric Acid Cycle. Accessed September 20, 2024. Available at: https://www.khanacademy.org/science/biology/cellular-respiration-and-fermentation/pyruvate-oxidation-and-the-citric-acid-cycle/a/the-citric-acid-cycle ↩︎
- Sugino T, Aoyagi S, Shirai T, Kajimoto Y, Kajimoto O. Effects of Citric Acid and l-Carnitine on Physical Fatigue. J Clin Biochem Nutr. 2007 Nov; 41(3): 224–230. Published online 2007 Oct 30. https://doi.org/10.3164/jcbn.2007032 PMCID: PMC2243251 ↩︎
- Hoy SM, Scott LJ, Wagstaff AJ. Sodium Picosulfate/Magnesium Citrate: A Review of Its Use as a Colorectal Cleanser. Drugs. 2009;69:123-136. Published online 17 September 2012. https://link.springer.com/article/10.2165/00003495-200969010-00009 ↩︎
- Public Health England. Government Dietary Recommendations: Government recommendations for energy and nutrients for males and females aged 1–18 years and 19+ years. Available at: https://assets.publishing.service.gov.uk/media/5a749fece5274a44083b82d8/government_dietary_recommendations.pdf ↩︎
- EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). Scientific Opinion on the substantiation of health claims related to magnesium and electrolyte balance, energy-yielding metabolism, neurotransmission and muscle contraction, cell division, maintenance of bone and teeth, blood coagulation, and protein synthesis pursuant to Article 13(1) of Regulation (EC) No 1924/2006. EFSA Journal, 2009;7(9):1216. DOI: https://doi.org/10.2903/j.efsa.2009.1216 ↩︎