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Magnesium 500 mg

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4.7
★ ★ ★ ★ ★
(30035 ratings)
Magnesium 500 mg
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Score74
Exceptionally cheap and simple, but the very high oxide dose favors label quantity over absorption and comfort.
How scoring works
Quantity:180 Tablet(s) • (180 servings)
Goals:
Digestive Health
General Health

Score 74

Exceptionally cheap and simple, but the very high oxide dose favors label quantity over absorption and comfort.
How scoring works
$7.87($0.04 per serving)
Vitacost
$ 8.69
Amazon
$ 0.00
iHerb
$ 7.87
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Analysis

The one-tablet formula is simple, inexpensive, and provides a very large elemental magnesium amount. A large bottle offers strong supply value.

Magnesium oxide is less efficiently absorbed than citrate, glycinate, or malate. Daily directions and full inactive ingredients are also absent from the supplied data.

The high amount may produce marked laxative effects and is not a gentle maintenance approach. Users prioritizing absorption or tolerance may prefer a smaller amount of a better form.

Who is it for
  • Budget users who tolerate magnesium oxide
  • Adults seeking a one-tablet high amount
Best for
  • Very low-cost supplementation
  • Large supply
  • Simple one-tablet use

Pros

  • Exceptionally low serving cost
  • One tablet daily
  • Large elemental amount
  • Large bottle

Cons

  • Poorly absorbed oxide
  • Very high serving amount
  • Directions and full excipients are missing

Warnings

  • The very high oxide dose may cause marked diarrhea or abdominal cramping.
  • People with impaired kidney function should not use high-dose magnesium without clinical guidance.

Nutrient quality

67 High impact

The elemental amount is substantial and the formula is focused. Poorly absorbed magnesium oxide and the high dose limit systemic usefulness and digestive tolerance.

Ingredient transparency

81 Highest impact

The active form and amount are clear without a hidden blend. Complete directions and tablet excipients are not supplied.

Customer satisfaction

71 High impact

The strong average rating and very large review count make the aggregate satisfaction signal reasonably dependable. No detailed review text was provided, so recurring complaints and purpose alignment cannot be assessed.

Value for money

75 High impact

The very low serving cost supports affordability, but the weak oxide form limits effective value. Better-absorbed magnesium products remain more competitive for systemic support.

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Goals

Digestive Health
Digestive Health
Impact
High effect
C+ Goal FitB- Strength of SupportD- CoverageA- Formula Quality
Magnesium · 500 mg

Magnesium oxide may promote bowel movement because much of it stays in the gut. That makes it relevant to occasional constipation but not broader digestive health.

The clearly disclosed amount is substantial and may produce a strong laxative effect. It can also cause diarrhea or abdominal cramping, especially in sensitive users.

Study evidence
Magnesium Supportive 50 studies
General Health
General Health
Impact
High effect
A Goal FitD Strength of SupportD CoverageB- Formula Quality
Magnesium · 500 mg

Magnesium is a highly relevant foundational mineral for energy production, nerve signaling, and muscle function. The label provides a substantial amount, but magnesium oxide is poorly absorbed compared with better organic or chelated forms.

A 500 mg supplemental serving may cause diarrhea or abdominal discomfort, especially when taken at once. The simple formula has clear intent, yet form quality and tolerability limit its value for routine general-health support.

Study evidence
Magnesium Supportive 114 studies
Cardiovascular Support
Cardiovascular Support
Impact
Moderate effect
B Goal FitD Strength of SupportD- CoverageA+ Formula Quality
Magnesium · 500 mg

Magnesium is relevant to vascular relaxation and normal heart rhythm, but magnesium oxide is poorly absorbed. The 500 mg amount is high enough to increase the chance of diarrhea or abdominal cramping without guaranteeing strong systemic delivery.

The single-mineral formula is focused and fully disclosed. It lacks lipid, nitric-oxide, antioxidant, and cardiac-energy support, so cardiovascular coverage remains narrow.

Study evidence
Magnesium Supportive 123 studies
Bone Health
Bone Health
Impact
Moderate effect
B Goal FitC- Strength of SupportD- CoverageC+ Formula Quality
Magnesium · 500 mg

Magnesium is relevant to bone structure and vitamin D metabolism. The amount is substantial, but dose alone does not overcome the form limitations.

Magnesium oxide has weak systemic absorption and may cause digestive discomfort at this amount. The product also lacks calcium, vitamin D, vitamin K, and bone-matrix cofactors.

Study evidence
Magnesium Supportive 48 studies
Energy
Energy
Impact
Moderate effect
B- Goal FitD Strength of SupportF CoverageA Formula Quality
Magnesium · 500 mg

Magnesium is relevant to ATP-dependent metabolism, but magnesium oxide has low systemic absorption. The 500 mg amount is high and may act more as a laxative than a reliable way to improve magnesium status.

The formula is simple and clearly labeled, with no unrelated energy ingredients or proprietary blends. It is a weak choice for targeted energy support despite its substantial stated amount.

Study evidence
Magnesium Supportive 4 studies
Heart Health
Heart Health
Impact
Moderate effect
B- Goal FitD- Strength of SupportD CoverageA- Formula Quality
Magnesium · 500 mg

Magnesium is relevant to vascular tone and normal heart rhythm, but oxide is poorly absorbed. A high label amount does not guarantee strong systemic magnesium support.

The single caplet clearly states the elemental amount and keeps the formula simple. The upper-edge oxide dose may cause loose stools without providing the advantages of a better-absorbed form.

Study evidence
Magnesium Supportive 158 studies

Ingredients

IngredientAmount per serving
Magnesium (Magnesium Oxide)
 500 mg
Gluten Free Adults 18–50 Dairy Free Sugar Free Vegetarian
Report overview
Magnesium (Magnesium Oxide) · 500 mg OverallScore45
F Active Ingredient Quality & BioavailabilityB Dose, Safety & Label TransparencyD- Value

Magnesium oxide has low systemic absorption despite clear elemental labeling. The serving sits at the upper edge and may be harder on digestion, with no supportive cofactor to improve the formula. Its very low cost is attractive, but the weak mineral form limits value for systemic magnesium support.

View ingredientView products
Loading alternative details
81 Performance

Ultra-Mag

Source Naturals
<p>A broad organic magnesium blend supplies strong form diversity and a substantial amount at an economical cost. Compared with Magnesium 500 mg, its magnesium form and supporting ingredients may be a better fit where the dose may cause diarrhea or cramping, while the simple tablet lacks any cofactor or gentler form, while the label does not clarify each form share, while high supplemental magnesium and prolonged B6 use may affect tolerability.</p>
85 Performance

Magnesium Bisglycinate Chelate

Healthy Origins
<p>TRAACS magnesium bisglycinate provides premium absorption quality, a useful elemental amount, and exceptional serving value in a clean powder. Compared with Magnesium 500 mg, its magnesium form and supporting ingredients may be a better fit where the dose may cause diarrhea or cramping, while the simple tablet lacks any cofactor or gentler form, while the product is narrow rather than comprehensive, and its relatively weak satisfaction metric deserves consideration despite the strong formula.</p>
75 Performance

NeuroMag

Designs for Health
<p>Branded magnesium L-threonate provides a well-characterized specialty form at its typical elemental amount. Compared with Magnesium 500 mg, its magnesium form and supporting ingredients may be a better fit where the dose may cause diarrhea or cramping, while the simple tablet lacks any cofactor or gentler form, while strong customer sentiment cannot fully offset a very high serving cost.</p>
80 Budget

Magnesium Caps 500 mg

Life Extension
<p>Citrate, succinate, and a named glycinate chelate strengthen a multi-form magnesium blend, while oxide lowers average absorption. The supplied data does not show a lower recurring cost than Magnesium 500 mg; it is among the closest low-cost eligible magnesium options, while the large supplemental amount may cause diarrhea or cramping, although the very low serving cost provides strong value for users who tolerate it.</p>
79 Budget

Target-Mins Magnesium Caps With Silica 300 mg

Country Life
<p>The mineral blend combines useful magnesium forms with oxide and a substantial horsetail-derived silica amount. The supplied data does not show a lower recurring cost than Magnesium 500 mg; it is among the closest low-cost eligible magnesium options, while strong customer sentiment and highly economical servings make the larger supply attractive.</p>
74 Budget

Magnesium 500 mg

Nature's Life
<p>Absorbable forms improve the blend, but magnesium oxide lowers its overall absorption quality. The supplied data does not show a lower recurring cost than Magnesium 500 mg; it is among the closest low-cost eligible magnesium options, while active doses are stated, while missing excipient and full use details limit transparency.</p>
84 Value

Magnesium Bisglycinate Chelate

Healthy Origins
<p>TRAACS magnesium bisglycinate provides premium absorption quality and a useful elemental amount in a clean tablet. Compared with Magnesium 500 mg, its magnesium profile offers a practical quality-to-cost trade-off despite no confirmed cost advantage, while the focused formula offers strong value but remains limited to one foundational mineral pathway.</p>
91 Value

Krebs Magnesium Potassium Complex

Nature's Way
<p>Magnesium lysinate and malate provide favorable forms at a useful amount, with a modest potassium contribution. Compared with Magnesium 500 mg, its magnesium profile offers a practical quality-to-cost trade-off despite no confirmed cost advantage, while the focused formula offers excellent serving value.</p>
88 Value

Magnesium Bisglycinate Powder

NOW
<p>Magnesium bisglycinate supplies a well-absorbed form at a practical, moderate amount. Compared with Magnesium 500 mg, its magnesium profile offers a practical quality-to-cost trade-off despite no confirmed cost advantage, while no meaningful dose or formulation concern is evident from the supplied facts.</p>
Report alternatives

Sources

Published studies used for the product analysis and the top-ranked studies for each ingredient and goal.

  1. The effect of food, vitamin, or mineral supplements on chronic constipation in adults: A systematic review and meta-analysis of randomized controlled trials.
    van der Schoot A; Creedon A; Whelan K; Dimidi E · Neurogastroenterology and motility · 2023
    Meta-analysis787 participants8 studies pooledDigestive Health forMagnesium
  2. A Randomized Double-blind Placebo-controlled Trial on the Effect of Magnesium Oxide in Patients With Chronic Constipation.
    Mori S; Tomita T; Fujimura K; Asano H; Ogawa T; Yamasaki T; Kondo T; Kono T; Tozawa K; Oshima T; Fukui H; Kimura T; Watari J; Miwa H · Journal of neurogastroenterology and motility · 2022
    Randomized trial34 participantsDigestive Health forMagnesium
  3. Diagnosis of magnesium-induced diarrhea.
    Fine KD; Santa Ana CA; Fordtran JS · The New England journal of medicine · 1991
    Clinical trial19 participantsDigestive Health forMagnesium
  4. Lactobacillus casei rhamnosus Lcr35 in children with chronic constipation.
    Bu LN; Chang MH; Ni YH; Chen HL; Cheng CC · Pediatrics international : official journal of the Japan Pediatric Society · 2007
    Randomized trial45 participantsDigestive Health forMagnesium
  5. Lactobacillus reuteri DSM 17938 and Magnesium Oxide in Children with Functional Chronic Constipation: A Double-Blind and Randomized Clinical Trial.
    Kubota M; Ito K; Tomimoto K; Kanazaki M; Tsukiyama K; Kubota A; Kuroki H; Fujita M; Vandenplas Y · Nutrients · 2020
    Randomized trial60 participantsDigestive Health forMagnesium
  6. Efficacy of oral magnesium therapy in the treatment of chronic constipation in spastic cerebral palsy children: a randomized controlled trial.
    Hassanein SMA; Deifallah SM; Bastawy HA · World journal of pediatrics : WJP · 2021
    Randomized trial100 participantsDigestive Health forMagnesium
  7. Magnesium-Rich Mineral Water Improves Stool Consistency and Bowel Habits in Healthy Subjects: A Randomized Controlled Trial.
    Yoneda H; Tomita T; Kitano T; Morishita D; Kodani M; Nishii N; Sei H; Eda H; Sato T; Kawai M; Yokoyama Y; Igeta M; Okugawa T; Fukui H; Shinzaki S · Neurogastroenterology and motility · 2026
    Randomized trial40 participantsDigestive Health forMagnesium
  8. Ca:Mg ratio, medium-chain fatty acids, and the gut microbiome.
    Fan L; Zhu X; Sun S; Yu C; Huang X; Ness R; Dugan LL; Shu L; Seidner DL; Murff HJ; Fodor AA; Azcarate-Peril MA; Shrubsole MJ; Dai Q · Clinical nutrition (Edinburgh, Scotland) · 2022
    Randomized trial240 participantsDigestive Health forMagnesium
  9. The Magnesium-Rich Formula for Functional Constipation in Infants: a Randomized Comparator-Controlled Study.
    Benninga MA; MENA Infant Constipation Study Group; Vandenplas Y · Pediatric gastroenterology, hepatology & nutrition · 2022
    Randomized trial286 participantsDigestive Health forMagnesium
  10. Effect of the laxative magnesium oxide on gastrointestinal functional recovery in fast-track colonic resection: a double-blind, placebo-controlled randomized study.
    Andersen J; Christensen H; Pachler JH; Hallin M; Thaysen HV; Kehlet H · Colorectal disease : the official journal of the Association of Coloproctology of Great Britain and Ireland · 2012
    Randomized trial49 participantsDigestive Health forMagnesium
  11. Association between Serum Magnesium and Fractures: A Systematic Review and Meta-Analysis of Observational Studies.
    Dominguez LJ; Veronese N; Ciriminna S; Pérez-Albela JL; Vásquez-López VF; Rodas-Regalado S; Di Bella G; Parisi A; Tagliaferri F; Barbagallo M · Nutrients · 2023
    Meta-analysis119,755 participants4 studies pooledBone Health forMagnesium
  12. Bioabsorbable Magnesium-Based Materials Potential and Safety in Bone Surgery: A Systematic Review.
    Hung CH; Kwok YC; Yip J; Wong HH; Leung YY · Craniomaxillofacial trauma & reconstruction · 2025
    Systematic review386 participants8 studies pooledBone Health forMagnesium
  13. Vascularized bone grafting fixed by biodegradable magnesium screw for treating osteonecrosis of the femoral head.
    Zhao D; Huang S; Lu F; Wang B; Yang L; Qin L; Yang K; Li Y; Li W; Wang W; Tian S; Zhang X; Gao W; Wang Z; Zhang Y; Xie X; Wang J; Li J · Biomaterials · 2016
    Randomized trial48 participantsBone Health forMagnesium
  14. An update on magnesium and bone health.
    Rondanelli M; Faliva MA; Tartara A; Gasparri C; Perna S; Infantino V; Riva A; Petrangolini G; Peroni G · Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · 2022
    Narrative reviewBone Health forMagnesium
  15. Sex-specific differences in the association of magnesium intake with femoral neck bone mineral density among older adults.
    Wang B; Tan X; Yao X; Zhu Z · Endocrine connections · 2025
    Cross-sectional study1,343 participantsBone Health forMagnesium
  16. Circulating and dietary magnesium and risk of cardiovascular disease: a systematic review and meta-analysis of prospective studies.
    Del Gobbo LC; Imamura F; Wu JH; de Oliveira Otto MC; Chiuve SE; Mozaffarian D · The American journal of clinical nutrition · 2013
    Meta-analysis313,041 participants16 studies pooledCardiovascular Support forMagnesium
  17. Magnesium and the risk of cardiovascular events: a meta-analysis of prospective cohort studies.
    Qu X; Jin F; Hao Y; Li H; Tang T; Wang H; Yan W; Dai K · PloS one · 2013
    Meta-analysis532,979 participants19 studies pooledCardiovascular Support forMagnesium
  18. Quantitative Association Between Serum/Dietary Magnesium and Cardiovascular Disease/Coronary Heart Disease Risk: A Dose-Response Meta-analysis of Prospective Cohort Studies.
    Zhao L; Hu M; Yang L; Xu H; Song W; Qian Y; Zhao M · Journal of cardiovascular pharmacology · 2020
    Meta-analysis544,581 participants18 studies pooledCardiovascular Support Heart Health forMagnesium
  19. Comparative Efficacy of Nutraceuticals on Endothelial Function: A Systematic Review and Network Meta-Analysis.
    Norouzzadeh M; Rashedi MH; Mahdavi-Mazdeh G; Kosari A; Shahinfar H · Current atherosclerosis reports · 2026
    Meta-analysisCardiovascular Support Heart Health forMagnesium
  20. Serum magnesium, mortality, and cardiovascular disease in chronic kidney disease and end-stage renal disease patients: a systematic review and meta-analysis.
    Xiong J; He T; Wang M; Nie L; Zhang Y; Wang Y; Huang Y; Feng B; Zhang J; Zhao J · Journal of nephrology · 2020
    Meta-analysis200,934 participants20 studies pooledCardiovascular Support forMagnesium
  21. Magnesium treatment increases gut microbiome synthesizing vitamin D and inhibiting colorectal cancer: results from a double-blind precision-based randomized placebo-controlled trial.
    Sun E; Zhu X; Ness RM; Murff HJ; Sun S; Yu C; Fan L; Azcarate-Peril MA; Shrubsole MJ; Dai Q · The American journal of clinical nutrition · 2025
    Randomized trial240 participantsDigestive Health forMagnesium
  22. Magnesium-L-threonate improves sleep quality and daytime functioning in adults with self-reported sleep problems: A randomized controlled trial.
    Hausenblas HA; Lynch T; Hooper S; Shrestha A; Rosendale D; Gu J · Sleep medicine: X · 2025
    Randomized trial80 participantsEnergy forMagnesium
  23. Total magnesium intake and risk of frailty in older women.
    Struijk EA; Fung TT; Bischoff-Ferrari HA; Willett WC; Lopez-Garcia E · Journal of cachexia, sarcopenia and muscle · 2024
    Cohort study81,524 participantsEnergy forMagnesium
  24. Red blood cell magnesium and chronic fatigue syndrome.
    Cox IM; Campbell MJ; Dowson D · Lancet (London, England) · 1991
    Randomized trial32 participantsEnergy forMagnesium
  25. Exercise, magnesium and immune function.
    Laires MJ; Monteiro C · Magnesium research · 2008
    Narrative reviewEnergy forMagnesium
  26. Perioperative systemic magnesium to minimize postoperative pain: a meta-analysis of randomized controlled trials.
    De Oliveira GS; Castro-Alves LJ; Khan JH; McCarthy RJ · Anesthesiology · 2013
    Meta-analysis1,257 participants20 studies pooledGeneral Health forMagnesium
  27. Long-term outcome after intravenous magnesium sulphate in suspected acute myocardial infarction: the second Leicester Intravenous Magnesium Intervention Trial (LIMIT-2).
    Woods KL; Fletcher S · Lancet (London, England) · 1994
    Randomized trial2,316 participantsGeneral Health forMagnesium
  28. Association of magnesium sulfate use with mortality in critically ill patients with sepsis: a retrospective propensity score-matched cohort study.
    Gu WJ; Duan XJ; Liu XZ; Cen Y; Tao LY; Lyu J; Yin HY · British journal of anaesthesia · 2023
    Cohort study10,999 participantsGeneral Health forMagnesium
  29. Hypomagnesemia and Mortality in Incident Hemodialysis Patients.
    Li L; Streja E; Rhee CM; Mehrotra R; Soohoo M; Brunelli SM; Kovesdy CP; Kalantar-Zadeh K · American journal of kidney diseases : the official journal of the National Kidney Foundation · 2016
    Cohort study9,359 participantsGeneral Health forMagnesium
  30. The effects of magnesium supplementation on abnormal uterine bleeding, alopecia, quality of life, and acne in women with polycystic ovary syndrome: a randomized clinical trial.
    Jaripur M; Ghasemi-Tehrani H; Askari G; Gholizadeh-Moghaddam M; Clark CCT; Rouhani MH · Reproductive biology and endocrinology : RB&E · 2022
    Randomized trial64 participantsGeneral Health forMagnesium
  31. Effects of magnesium supplementation on improving hyperglycemia, hypercholesterolemia, and hypertension in type 2 diabetes: A pooled analysis of 24 randomized controlled trials.
    Xu L; Li X; Wang X; Xu M · Frontiers in nutrition · 2023
    Meta-analysis1,325 participants24 studies pooledHeart Health forMagnesium
  32. The effect of lowering blood pressure by magnesium supplementation in diabetic hypertensive adults with low serum magnesium levels: a randomized, double-blind, placebo-controlled clinical trial.
    Guerrero-Romero F; Rodríguez-Morán M · Journal of human hypertension · 2009
    Randomized trial82 participantsHeart Health forMagnesium
  33. Positive effects of magnesium supplementation in metabolic syndrome.
    Kisters S; Kisters K; Werner T; Vormann J; Tokmak F; Westhoff T; Gröber U; Predel HG; Reuter H · International journal of clinical pharmacology and therapeutics · 2024
    Randomized trial54 participantsHeart Health forMagnesium
  34. Role of magnesium supplementation in the treatment of depression: A randomized clinical trial.
    Tarleton EK; Littenberg B; MacLean CD; Kennedy AG; Daley C · PloS one · 2017
    Randomized trial126 participantsStress Relief forMagnesium
  35. Effects of Intravenous Esketamine or Magnesium Sulfate on Early Postoperative Negative Emotions and Pain in Patients Undergoing Endoscopic Sinus Surgery: A Randomized Controlled Trial.
    Wang L; Zhou J; Liu Q; Qian K; Wang L; Xie C · Therapeutics and clinical risk management · 2026
    Randomized trial137 participantsStress Relief forMagnesium
  36. Effect of short-term magnesium supplementation on anxiety, depression and sleep quality in patients after open-heart surgery.
    Saba S; Faizi F; Sepandi M; Nehrir B · Magnesium research · 2022
    Non-randomized trial60 participantsStress Relief forMagnesium
  37. Effects of dry needling compared to magnesium infiltration in trigger points for patients with myofascial pain syndrome: a randomized controlled study in Tunisia.
    Dhouibi J; Moncer R; Kalbousi N; Gaddour M; Laayouni S; Ouanes W; Kacem B; Jemni S · Korean journal of family medicine · 2026
    Randomized trial45 participantsStress Relief forMagnesium
  38. 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.
    Noah L; Dye L; Bois De Fer B; Mazur A; Pickering G; Pouteau E · Stress and health : journal of the International Society for the Investigation of Stress · 2021
    Randomized trialStress Relief forMagnesium
  39. Magnesium and anabolic hormones in older men.
    Maggio M; Ceda GP; Lauretani F; Cattabiani C; Avantaggiato E; Morganti S; Ablondi F; Bandinelli S; Dominguez LJ; Barbagallo M; Paolisso G; Semba RD; Ferrucci L · International journal of andrology · 2012
    Cohort study399 participantsTestosterone Support forMagnesium
  40. Analysis of the relationship between the blood concentration of several metals, macro- and micronutrients and endocrine disorders associated with male aging.
    Rotter I; Kosik-Bogacka DI; Dołęgowska B; Safranow K; Kuczyńska M; Laszczyńska M · Environmental geochemistry and health · 2017
    Cross-sectional study313 participantsTestosterone Support forMagnesium
  41. Effect of magnesium supplementation in improving hyperandrogenism, hirsutism, and sleep quality in women with polycystic ovary syndrome: A randomized, placebo-controlled clinical trial.
    Gholizadeh-Moghaddam M; Ghasemi-Tehrani H; Askari G; Jaripur M; Clark CCT; Rouhani MH · Health science reports · 2024
    Randomized trial64 participantsTestosterone Support forMagnesium
  42. The effects of trace element supplementation on glycolipid metabolism in PCOS: a systematic review and meta-analysis.
    Yang L; Gao Y; Zhao W; Qi Y; Duo X; Wang H · Frontiers in nutrition · 2025
    Meta-analysis1,600 participants25 studies pooledTestosterone Support forMagnesium
  43. Effects of magnesium supplementation on testosterone levels of athletes and sedentary subjects at rest and after exhaustion.
    Cinar V; Polat Y; Baltaci AK; Mogulkoc R · Biological trace element research · 2011
    Non-randomized trial20 participantsTestosterone Support forMagnesium