As a Registered Dietitian, I spend a lot of my time talking about nutrients that quietly do a lot of heavy lifting. Magnesium is at the top of that list. This mineral participates in more than 300 enzymatic reactions in the body, affecting everything from energy production to muscle and nerve function.
Most people know magnesium for its role in relaxation and better sleep. That's real, but it's only part of the story. In my practice, I've seen how the broader magnesium benefits often surprise people. Below, I'll walk you through five lesser-known ways this mineral supports your health, backed by what the research actually shows.
1. May Help Support Healthy Blood Sugar Regulation
Magnesium is involved in insulin signaling and glucose metabolism, which means it plays a real role in how your body processes the food you eat. Research has linked low magnesium status to reduced insulin sensitivity, and reviews of controlled trials suggest that supplementation may support healthier fasting glucose and insulin-sensitivity markers, particularly in people who are running low on the mineral.1 A 2025 meta-analysis also found modest improvements in glucose measures in people with type 2 diabetes who supplemented with magnesium.2
One study evaluated whether taking magnesium supplements could help control blood sugar in people who have diabetes or who are at high risk of getting it. Results showed that, in people with diabetes, magnesium supplementation was linked to lower fasting blood sugar (the level measured before eating) than those on a placebo. Results also showed that people at high risk of diabetes had better blood sugar levels after a sugar-drink test, along with early signs that their bodies may use insulin a little more effectively.3
Another study evaluated the effects of a daily magnesium supplement on blood sugar control in older adults who have pre-diabetes and low magnesium levels. Results showed that, over 16 weeks, taking magnesium supplements was linked to lower fasting blood sugar than taking a placebo.4
Bottom line? Supporting healthy blood sugar balance can mean fewer energy crashes and fewer sugar cravings in the afternoon. That's not a minor thing. Magnesium is not a treatment for diabetes, and I always pair this conversation with a reminder to work with your healthcare provider. But from a foundational nutrition standpoint, keeping your magnesium levels adequate is a smart move for metabolic health.
2. Helps Support a Healthy Stress Response
Magnesium's relationship with stress is more nuanced than most people realize. Yes, it helps with relaxation, but it also plays a direct role in how your nervous system handles pressure. Magnesium supports GABA activity, which is a calming neurotransmitter in the brain, and it helps modulate the release of cortisol, your body's primary stress hormone.
What makes this especially interesting is what researchers describe as a potential "vicious circle": stress appears to increase magnesium loss through the body, and low magnesium may make you more susceptible to stress in return.5 It's a bidirectional relationship that isn't fully settled in the science, but the practical implication is clear. When life gets demanding, keeping your magnesium intake consistent is one of the more sensible nutritional habits you can create.
3. May Help Reduce Migraine Frequency
If you or someone you know deals with migraines, this one is worth knowing. Lower magnesium levels have been associated with a higher tendency toward migraines, and researchers have been studying the mineral as part of a prevention approach for decades.6 When magnesium levels are low, the brain may become more excitable, which can make some people more prone to migraines.
A 2025 review found that oral magnesium supplementation may help reduce the frequency and intensity of migraine attacks in some people, particularly those who tend to run low on the mineral.6 If you experience frequent migraines, bring this up with your healthcare provider. It can be a valuable part of a broader management plan.
4. May Help Ease PMS Symptoms
Many of my clients ask about magnesium for PMS, and it's a reasonable area to explore. Magnesium plays a role in muscle relaxation and nervous system regulation, both of which are relevant to symptoms that appear in the days before your period, including cramps, mood changes, and more.
The evidence here is still developing. A 2019 systematic review found that women with PMS had lower serum magnesium levels.7 Some research also suggests that pairing magnesium with vitamin B6 may offer additional support for mood-related symptoms.8
My take: it's not a guaranteed fix, but focusing on consistent, adequate magnesium throughout the month is a reasonable, practical habit. As always, if PMS symptoms are significantly affecting your quality of life, talk to your provider about a comprehensive approach.
5. Supports Digestive Regularity
This is one of the most talked-about benefits of magnesium, and for good reason. Certain forms act as osmotic laxatives, drawing water into the intestines to soften stool and promote bowel movement.
Magnesium citrate is one of the most commonly used forms for this purpose and is often considered a gentler, more accessible alternative to other osmotic options such as polyethylene glycol. Research has also found that magnesium oxide can be effective for chronic constipation in adults, with meaningful improvements in bowel movement frequency and quality of life compared to placebo.9 The form you choose matters, though. Different types of magnesium are better suited to different goals; some support relaxation or cognitive function, while others are specifically well-suited for digestive support.
The Bottom Line on Magnesium
Magnesium touches so many areas of health that it's one of the first nutrients I look at when something feels off. From blood sugar management support to migraine management and more, this mineral has a hand in it all. And yet, inadequate magnesium intake is surprisingly common.
Start with food first. Leafy greens, nuts, seeds, legumes, and whole grains are all solid sources. But if your diet consistently falls short (and most of ours do), a quality supplement can help fill the gap. Small, steady habits like this are the foundation of long-term wellness.
Find the Magnesium That Fits Your Needs
Not all magnesium supplements are created equal. In fact, the form you take can make a real difference in how well your body absorbs and uses it.
Doctor's Best High Absorption Magnesium products are available in several forms, each designed with bioavailability and GI tolerance in mind. Magnesium Citrate is a great option if digestive support and muscle relaxation are your priorities. Magnesium L-Threonate is worth considering if cognitive function is top of mind.
Matching your supplement to your personal wellness goals makes the whole thing feel a lot more intentional, and a lot less like guesswork. As always, your healthcare provider can help you figure out what makes the most sense for you.
Shop Doctor's Best Magnesium Products
Frequently Asked Questions
What are the main benefits of magnesium?
Magnesium supports hundreds of processes in the body, including muscle and nerve function, energy production, healthy blood sugar balance, stress resilience, and digestive regularity. It's also well known for supporting relaxation and sleep.
Which form of magnesium is best for constipation?
Magnesium citrate is a common choice for digestive support because it works as an osmotic laxative. Magnesium oxide has also been studied for chronic constipation and may be a good option depending on your needs.
Can you take magnesium every day?
For most healthy adults, daily magnesium intake from food and supplements, within recommended limits, is generally considered safe. Individual needs vary, so check with your healthcare provider before starting any new supplement routine.
REFERENCES
1 Veronese, N., Dominguez, L. J., Pizzol, D., Demurtas, J., Smith, L., & Barbagallo, M. (2021). Oral Magnesium Supplementation for Treating Glucose Metabolism Parameters in People with or at Risk of Diabetes: A Systematic Review and Meta-Analysis of Double-Blind Randomized Controlled Trials. Nutrients, 13(11), 4074. https://doi.org/10.3390/nu13114074
2 Maqrashi, Nasiba Al; Busaidi, Salim Al; Al-Rasbi, Sara; Alawi, Abdullah M. Al; and Al-Maqbali, Juhaina S. (2025) "Effect of Magnesium Supplements on Improving Glucose Control, Blood Pressure and Lipid Profile in Patients With Type 2 Diabetes Mellitus: A systematic review and meta-analysis," Sultan Qaboos University Medical Journal: Vol. 25: 382-394.
DOI: https://doi.org/10.18295/2075-0528.2848
3 Veronese, N., Watutantrige-Fernando, S., Luchini, C., Solmi, M., Sartore, G., Sergi, G., Manzato, E., Barbagallo, M., Maggi, S., & Stubbs, B. (2016). Effect of magnesium supplementation on glucose metabolism in people with or at risk of diabetes: a systematic review and meta-analysis of double-blind randomized controlled trials. European journal of clinical nutrition, 70(12), 1354–1359. https://doi.org/10.1038/ejcn.2016.154
4Yang J, Zhang H, Li Y, Wu W, Pan M, Wang J, Li G, Wu Y, Guo C, Yang L, Ding J and Ding G (2026) Oral magnesium supplementation improves glycemic control in older Chinese adults with pre-diabetes and hypomagnesemia: a randomized controlled trial. Front. Nutr. 13:1765308. doi: 10.3389/fnut.2026.1765308
5 Pickering, G., Mazur, A., Trousselard, M., Bienkowski, P., Yaltsewa, N., Amessou, M., Noah, L., & Pouteau, E. (2020). Magnesium Status and Stress: The Vicious Circle Concept Revisited. Nutrients, 12(12), 3672. https://doi.org/10.3390/nu12123672
6 Dominguez, L. J., Veronese, N., Sabico, S., Al-Daghri, N. M., & Barbagallo, M. (2025). Magnesium and Migraine. Nutrients, 17(4), 725. https://doi.org/10.3390/nu17040725
7 Moslehi, M., Arab, A., Shadnoush, M. et al. The Association Between Serum Magnesium and Premenstrual Syndrome: a Systematic Review and Meta-Analysis of Observational Studies. Biol Trace Elem Res 192, 145–152 (2019). https://doi.org/10.1007/s12011-019-01672-z
8 Noah, L., Dye, L., Bois De Fer, B., Mazur, A., Pickering, G., & Pouteau, E. (2021). Effect of magnesium and vitamin B6 supplementation on mental health and quality of life in stressed healthy adults: Post-hoc analysis of a randomised controlled trial. Stress and health : journal of the International Society for the Investigation of Stress, 37(5), 1000–1009. https://doi.org/10.1002/smi.3051
9 Bassotti, G., Villanacci, V., & Corsetti, M. (2023). Exploring Pharmacological Treatments for Chronic Idiopathic Constipation in Adults: A Look Back to the Future. Journal of clinical medicine, 12(4), 1702. https://doi.org/10.3390/jcm12041702
About the Author
Lauren Manaker, MS, RDN, LD, CLEC, is an award-winning registered dietitian and three-time book author focused on providing clear and evidence-based nutrition guidance. Practicing since 2004, she holds degrees in Human Nutrition from the University of Florida and Clinical Nutrition from Rush University. A trusted medical reviewer and contributor to outlets like Good Housekeeping, Prevention, and Eating Well, Lauren is also a speaker who presents at professional health-focused conferences across the nation.