Not all magnesium supplements are created equal — and with hundreds of products on the market, working out which one is actually right for you can feel like a job in itself.
Magnesium comes in a wide range of forms, each one bonded to a different compound. That pairing changes how well the magnesium is absorbed, how gentle it is on your stomach, and in some cases, what else it may bring to the table — whether that’s for sleep, energy, muscles, or something else entirely.
In this guide, we compare five popular magnesium supplements from trusted brands in the UK — including one of our own. Our aim isn’t to crown a single “best” — it’s to help you understand the different forms available, see how a few well-regarded products actually stack up, and find the one that fits what you’re looking for.
Quick Comparison Table
Here’s a quick comparison of the five magnesium supplements covered in this guide.
| Product | Form | Elemental Magnesium | Price | Price per 100mg |
|---|---|---|---|---|
| MAGSUPPS Magnesium Glycinate | Glycinate | 100mg per capsule | £15.95 | £0.18 |
| BioCare Magnesium Malate | Malate | 117mg per capsule | £16.99 | £0.16 |
| Time Health Magtein | L-threonate | 37.75mg per capsule | £25.49 | £0.56 |
| Viridian Magnesium Taurate | Taurate | 56mg per capsule | £29.35 | £0.58 |
| Lamberts MagAsorb Magnesium Citrate | Citrate | 375mg per scoop | £22.95 | £0.20 |
Why Magnesium Matters
Magnesium is an essential mineral, acting as a cofactor in over 300 enzymatic processes throughout the body1. As per EFSA-authorised health claims, magnesium contributes to:
- Muscle, nerve, and psychological function
- Energy-yielding metabolism and electrolyte balance
- Reduction of tiredness and fatigue
- Maintenance of bones and teeth
- Protein synthesis and cell division
Despite its importance, deficiency is more common than most people realise. Research suggests that between 2.5% and 15% of people in the UK meet the criteria for clinical magnesium deficiency2, while many more may have suboptimal intake without knowing it. Modern diets high in processed foods, chronic stress, certain medications, and alcohol consumption can all deplete magnesium levels — often gradually and without obvious symptoms.
When magnesium intake is low, it can affect multiple systems at once. Muscle cramps, fatigue, poor sleep, headaches, and low mood are among the most commonly reported signs — though they’re easy to attribute to other causes, which is why deficiency often goes unnoticed.
Choosing the right magnesium supplement can make a meaningful difference — and it starts with understanding the different forms available.
5 of the Best Magnesium Supplements in the UK
All magnesium supplements come in the form of a compound, where magnesium is bound to another substance. This combination affects how well the magnesium is absorbed and tolerated by the body, as well as any additional or synergistic properties the supplement may offer.
Below, we’ll cover five of the most popular forms of magnesium, across various products from trusted UK brands — so you can learn the differences between them, and how they compare as actual products.
MAGSUPPS Magnesium Glycinate
Magnesium glycinate — also known as magnesium bisglycinate — is one of the most widely used chelated forms of magnesium in the UK, commonly chosen for general daily supplementation, and for relaxation and sleep specifically.
It’s created by binding magnesium to glycine, an amino acid that acts as an inhibitory neurotransmitter within the central nervous system3. This chelated structure is associated with good absorption and a gentler effect on digestion than less bioavailable forms like magnesium oxide. Glycine itself has been studied for its potential role in relaxation and sleep quality4 5 — part of why this form is commonly chosen for evening use.
MAGSUPPS Magnesium Glycinate delivers 100mg of elemental magnesium from 750mg of magnesium glycinate per capsule — a 13.3% elemental figure, within the pure, non-buffered range for this form. Many magnesium glycinate supplements sold in the UK are buffered — blended with magnesium oxide to artificially inflate the elemental magnesium figure on the label — so it’s worth checking for on any product, not just this one. This formula contains just two ingredients: magnesium glycinate and a vegan capsule shell, free from fillers and magnesium oxide.
Every batch is independently third-party tested, with lab results published by batch number directly on the MAGSUPPS website.
Key Highlights:
- £15.95 per pouch (90 capsules)
- 100mg elemental magnesium from 750mg of magnesium glycinate per capsule (13.3%)
- 100% pure, non-buffered — free from fillers and magnesium oxide
- Third-party batch tested, with lab reports published online
- UK-made, eco-friendly pouch packaging
Available from: Amazon
BioCare Magnesium Malate
Magnesium malate is a highly bioavailable form of magnesium, commonly chosen for energy production, muscle function, and exercise recovery. It combines magnesium with malic acid, a compound naturally found in fruits such as apples and pears.
Malic acid plays a role in the Krebs cycle6 — the body’s process for converting food into usable cellular energy. Alongside magnesium’s own contribution to normal muscle function and the reduction of tiredness and fatigue, research has also looked at whether malic acid and magnesium supplementation may support athletic performance and recovery after exercise7 8, which is part of why this form is often associated with active lifestyles.
BioCare Magnesium Malate delivers 117mg of elemental magnesium alongside 720mg of malic acid per capsule. The formula also includes a bulking agent (cellulose), an antioxidant (ascorbyl palmitate), and rice hull. BioCare is a UK supplement brand with over 30 years in the industry.
Key Highlights:
- £16.99 per pouch (90 capsules)
- 117mg elemental magnesium from 720mg of malic acid per capsule
- Recyclable packaging
- Established UK brand, 30+ years
Time Health Magnesium L-Threonate
Magnesium L-threonate is a specialised form of magnesium invented by Dr. Guosong Liu, a former MIT professor, and sold under the patented name Magtein®. It’s created by combining magnesium with threonic acid, a metabolite of vitamin C — a pairing developed specifically to cross the blood-brain barrier and deliver magnesium directly to brain tissue9.
In a notable human study10, participants taking magnesium L-threonate showed improvements across several measures of cognitive function — including attention, processing speed, task switching, and executive function — alongside measurable changes in functional brain age over the course of the trial. Further research has also looked at magnesium L-threonate’s potential role in relaxation and sleep quality11.
Time Health Magnesium L-Threonate uses Magtein and a pullulan capsule shell with no fillers or unnecessary additives — each 4-capsule serving delivers 2,100mg of Magtein, providing 151mg of elemental magnesium.
It’s worth noting: magnesium L-threonate is a specialist form, designed to target the brain rather than maximise overall elemental magnesium intake — so don’t be put off by the lower elemental figure compared to forms like glycinate or malate. This is the dose level used in the clinical research behind the ingredient, not a sign of a weaker product.
Key Highlights:
- £25.49 per pouch (30 servings)
- 2,100mg Magtein per serving, providing 151mg of elemental magnesium
- Two ingredients: Magtein and a pullulan capsule shell
- Magtein® is the only form of magnesium L-threonate currently approved as a novel food by the UK FSA
- UK manufactured, GMP certified
Viridian Magnesium Taurate
Magnesium taurate is a gentle, highly bioavailable form of magnesium, commonly chosen for cardiovascular support and relaxation. It combines magnesium with taurine, one of the most abundant amino acids in the human body, found in particularly high concentrations in the heart, brain, eyes, and muscles12.
Unlike amino acids primarily used to build proteins, taurine plays a role in a range of physiological functions13, and has been studied for its potential calming effects on the nervous system — research suggests it may support relaxation by interacting with GABA14, the body’s primary inhibitory neurotransmitter. This dual profile is part of why magnesium taurate is often associated with both heart health and a sense of calm.
Viridian Magnesium Taurate delivers 112mg of elemental magnesium from 1,500mg of magnesium taurate per serving of two capsules. The formula contains 100% active ingredients — no fillers or artificial additives — formulated by nutritionists and sourced to Viridian’s ethical criteria, including no animal testing, no GMO, and no palm oil. It’s BRC certified to AA grade, and packaged in recyclable glass jars.
Key Highlights:
- £29.35 per jar (90 capsules)
- 112mg elemental magnesium from 1,500mg of magnesium taurate per two-capsule serving
- 100% active ingredients — no fillers or artificial additives
- BRC certified AA grade manufacturing standards
- Recyclable glass jar packaging
Lambert’s MagAsorb Magnesium Citrate
Magnesium citrate is a widely used, highly bioavailable form of magnesium, commonly chosen for energy production, muscle function, and general daily supplementation. It combines magnesium with citric acid, the compound found naturally in citrus fruits, which helps improve the solubility and absorption of magnesium in the body.
Citric acid also plays a role in cellular energy production through the Krebs cycle15, part of why magnesium citrate is often associated with energy and general vitality.
Magnesium citrate is sometimes associated with digestive discomfort, but this is often a case of dose rather than the form itself. In the United States, high-dose liquid magnesium citrate products are commonly sold specifically as laxatives, providing extremely large doses — often between 1,885mg and 2,900mg per serving — far exceeding standard supplemental amounts. At typical supplemental doses, magnesium citrate is generally well tolerated.
Lambert’s MagAsorb Magnesium Citrate delivers 375mg of elemental magnesium per 5.5g scoop — 100% of the adult NRV in a single serving. It’s a fizzy, citrus-flavoured powder, mixed into water, with no added sugar. A scoop is provided in the pot, and it’s suitable for vegetarians and vegans. Unlike a tablet or capsule, it’s an option worth considering for anyone who finds swallowing pills difficult, or who prefers a single high-strength daily serving over multiple capsules.
Key Highlights:
- £22.95 per pot (165g, roughly a 1-month supply)
- 375mg elemental magnesium per 5.5g scoop (100% of adult NRV)
- Citrus flavour, no added sugar, sweetened with sucralose
- Suitable for vegetarians and vegans
- Powder format — an alternative for those who struggle with tablets or capsules
How to Choose the Right Magnesium Supplement for You
With so many magnesium supplements available in the UK, choosing the right product can feel overwhelming. Understanding what to look for can help you find one that’s effective, high-quality, and well formulated.
Choose the Right Type of Magnesium
As covered above, different forms of magnesium vary in absorption, digestive tolerance, and intended use — some are better suited to relaxation and sleep, others to energy production, muscle function, cognitive support, or general daily supplementation.
It’s also worth knowing that different forms can be combined for complementary benefits. One popular combination is magnesium glycinate, malate, and citrate — as found in our own MAGSUPPS Triple Magnesium Complex — designed for broad, all-round daily support. Another common pairing is glycinate, taurate, and L-threonate, aimed more specifically at relaxation and cognitive support.
Avoid Buffered Magnesium Supplements
Many magnesium supplements sold in the UK are buffered — blended with magnesium oxide, a cheaper, poorly absorbed form, often used to inflate the elemental magnesium figure on the label. A fully chelated, non-buffered supplement is generally the better option for absorption and digestive comfort. Learn more about buffered vs non-buffered magnesium.
Check Manufacturing and Ingredient Quality
High-quality magnesium supplements are typically manufactured in well-regulated regions such as the UK, EU, and USA, to recognised standards like GMP, HACCP, or ISO certification. It’s also worth checking the full ingredients list — unnecessary fillers, binders, or flow agents add little beyond manufacturing convenience.
Check for Third-Party Lab Testing
Third-party testing helps verify a supplement’s purity, potency, and safety — including checks for heavy metals and microbial contamination. Brands that openly publish their test results are generally demonstrating a stronger commitment to transparency.
Frequently Asked Questions
How much magnesium do I need per day?
The official UK dietary recommendations set the suggested daily intake at 300mg for men and 270mg for women aged 19–64. Requirements vary by age — children need less, and teenagers approaching adulthood need amounts closer to adult levels.
Can I get enough magnesium from my diet?
In theory, yes. Magnesium-rich foods include nuts and seeds, leafy greens, whole grains, legumes, dark chocolate, and fatty fish. However, modern diets high in processed foods are often lower in magnesium than they once were, and factors like chronic stress and certain medications can deplete levels further.
What are the benefits of magnesium supplements?
In the UK, supplement health claims are regulated — only benefits formally reviewed and authorised by EFSA are permitted. For magnesium, these include contributions to normal muscle and nerve function, normal psychological function, reduction of tiredness and fatigue, normal energy-yielding metabolism, electrolyte balance, and the maintenance of normal bones and teeth.
How long do magnesium supplements take to work?
Some people notice a difference within a few days, while for others it can take several weeks of consistent use. One factor that may influence this is whether you’re deficient to begin with — those with lower magnesium levels may notice effects sooner. Consistent daily use over several weeks is the most important factor.
What are the risks and side effects of magnesium supplements?
Magnesium supplements are generally safe for most healthy adults at recommended doses. According to the NHS, taking more than 400mg per day from supplements can cause diarrhoea in some people. To avoid this, stick to the recommended dose on your supplement label, or follow the advice of a healthcare professional.
Should I take a magnesium supplement?
If you’re not consistently meeting your magnesium needs through diet alone, a supplement is a practical way to support your daily intake. As always, it’s worth speaking to a healthcare professional before starting any new supplement — particularly if you’re pregnant, breastfeeding, or taking prescribed medication.
The Bottom Line
Magnesium supplements come in a genuinely wide range of forms, and there’s no single “best” one — just the one that fits what you’re actually looking for.
Glycinate is a widely used, well-tolerated option suited to everyday use and evening routines. Citrate offers a highly absorbable, versatile choice, including in powder form for anyone who’d rather not take capsules or tablets. Malate is often chosen alongside an active lifestyle. Taurate pairs magnesium with an amino acid found in high concentrations in the heart, and L-threonate is a specialist form developed specifically to target the brain — worth knowing it typically delivers a lower elemental figure by design, not by compromise.
Whichever form you’re drawn to, look beyond the marketing and check the label: the elemental magnesium per serving, the presence (or absence) of fillers and additives, and whether the brand backs its formula with independent, third-party testing.
As always, speak to a healthcare professional before starting any new supplement, particularly if you’re pregnant, breastfeeding, or taking prescribed medication.
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 ↩︎
- Ayuk J, Gittoes NJL. How should hypomagnesaemia be investigated and treated? Clin Endocrinol (Oxf). 2011;75(6):743-6. https://doi.org/10.1111/j.1365-2265.2011.04092.x ↩︎
- López-Corcuera B, Geerlings A, Aragón C. Glycine neurotransmitter transporters: an update. Mol Membr Biol. 2001;18(1):13-20. https://pubmed.ncbi.nlm.nih.gov/11396606/ ↩︎
- Razak, M. A., et al. Multifarious beneficial effect of nonessential amino acid, glycine: A review. Oxidative Medicine and Cellular Longevity, 2017. https://doi.org/10.1155/2017/1716701 ↩︎
- Yamadera, W., et al. Glycine ingestion improves subjective sleep quality in human volunteers. Sleep and Biological Rhythms, 5, 126–131. 2007. https://doi.org/10.1111/j.1479-8425.2007.00262.x ↩︎
- PubChem. Malic Acid. https://pubchem.ncbi.nlm.nih.gov/compound/Malic-acid ↩︎
- Fu Qiang. Effect of Malate-oligosaccharide Solution on Antioxidant Capacity of Endurance Athletes. The Open Biomedical Engineering Journal. 2015. https://openbiomedicalengineeringjournal.com/VOLUME/9/PAGE/326/ ↩︎
- Setaro L, et al. Magnesium status and the physical performance of volleyball players. J Sports Sci. 2014;32(5):438-45. https://doi.org/10.1080/02640414.2013.828847 ↩︎
- Slutsky, I., et al. Enhancement of Learning and Memory by Elevating Brain Magnesium. Neuron, 65(2), 165-177. 2010. https://doi.org/10.1016/j.neuron.2009.12.026 ↩︎
- Liu, G., et al. Efficacy and Safety of MMFS-01, a Synapse Density Enhancer, for Treating Cognitive Impairment in Older Adults. Journal of Alzheimer’s Disease, 49(4), 971-990. 2016. https://doi.org/10.3233/JAD-150538 ↩︎
- Hausenblas, H. A., Lynch, T., Hooper, S., Shrestha, A., Rosendale, D., & Gu, J. (2024). Magnesium-L-threonate improves sleep quality and daytime functioning in adults with self-reported sleep problems: A randomized controlled trial. Sleep Medicine: X, 8, 100121. https://doi.org/10.1016/j.sleepx.2024.100121 ↩︎
- Liu, G., et al. Efficacy and Safety of MMFS-01, a Synapse Density Enhancer, for Treating Cognitive Impairment in Older Adults. Journal of Alzheimer’s Disease, 49(4), 971-990. 2016. https://doi.org/10.3233/JAD-150538 ↩︎
- Jong, C. J., Sandal, P., & Schaffer, S. W. The Role of Taurine in Mitochondria Health. Molecules. 2021;26(16):4913. https://doi.org/10.3390/molecules26164913 ↩︎
- Ochoa-de la Paz, L., et al. Taurine and GABA neurotransmitter receptors, a relationship with therapeutic potential? Expert Review of Neurotherapeutics. 2019;19(4):289-291. https://doi.org/10.1080/14737175.2019.1593827 ↩︎
- PubChem. Citric Acid. https://pubchem.ncbi.nlm.nih.gov/compound/Citric-Acid ↩︎