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MagSRT B-Free

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(3006 ratings)
Magnesium 500 mg
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Score77
A clearly labeled magnesium malate formula offers useful absorption, but its high dose, four-tablet serving, and cost reduce practicality.
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Tablet
Quantity:240 Tablet(s) • (60 servings)
Goals:
Energy
Heart Health
Sleep Support
Stress Relief
Testosterone Support
General Health
Cardiovascular Support

Score 77

A clearly labeled magnesium malate formula offers useful absorption, but its high dose, four-tablet serving, and cost reduce practicality.
How scoring works
$49.97($0.83 per serving)
iHerb
$ 49.97
Amazon
$ 49.97
Walmart
$ 49.97
iHerb
$ 49.97
Pure Formulas
$ 49.97
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Analysis

The serving provides 500 mg of magnesium from dimagnesium malate plus 1,436 mg of malic acid. Malate is a reasonable form for systemic magnesium support, and the label separates elemental magnesium from the larger compound contribution.

Sustained-release positioning may appeal to people who prefer gradual delivery, although no patented raw-material standard is supplied. Four tablets per serving create a meaningful pill burden.

It best fits users who specifically want malate and tolerate a high amount. Many people can meet routine needs with a smaller serving or a less expensive malate product.

Who is it for
  • Adults specifically seeking magnesium malate
  • People comfortable with a four-tablet serving
  • Users who tolerate high-dose magnesium
Best for
  • Systemic magnesium support
  • Malate-focused supplementation
  • People who prefer extended-release tablets

Pros

  • Uses dimagnesium malate
  • Clearly discloses elemental magnesium
  • Separately states malic acid
  • Avoids added B vitamins

Cons

  • 500 mg is above many routine needs
  • Requires four tablets per serving
  • Serving cost is high
  • No patented malate material is identified

Warnings

  • The 500 mg serving of supplemental magnesium may cause loose stools, cramping, or nausea; a smaller divided amount may be easier to tolerate.
  • Magnesium can reduce absorption of tetracycline or quinolone antibiotics; follow the prescriber or pharmacist’s spacing instructions.
  • Magnesium can interfere with levothyroxine absorption and should be separated according to medication guidance.
  • People with significantly reduced kidney function can accumulate magnesium and need clinician-guided use.

Nutrient quality

79 High impact

Dimagnesium malate is a well-absorbed organic mineral form. The elemental magnesium amount is substantial and slightly aggressive for routine supplementation, while the large amount may be difficult to tolerate and can loosen stools in sensitive users.

Ingredient transparency

81 Highest impact

Elemental magnesium and the larger malate compound amount are both stated clearly. Serving totals are apparent, but full directions and inactive ingredients are not supplied.

Customer satisfaction

71 High impact

The supplied average rating is strong. The very large rating base makes the average unusually stable, while complaint and firsthand experience details are unavailable.

Value for money

73 High impact

Formula quality supports the asking position well. The serving value is reasonably competitive within the category.

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Goals

Energy
Energy
Impact
Highest effect
B Goal FitA Strength of SupportC- CoverageA+ Formula Quality
Magnesium · 500 mg

Magnesium malate supports reactions involved in cellular energy production and may help when low magnesium contributes to fatigue. The formula is focused and free of stimulants, but it addresses only one energy pathway.

Dimagnesium malate is a useful form with a clearly stated elemental amount. The 500 mg magnesium serving may cause diarrhea or stomach discomfort in sensitive users.

Study evidence
Magnesium Supportive 4 studies
Heart Health
Heart Health
Impact
High effect
B+ Goal FitB+ Strength of SupportD+ CoverageA Formula Quality
Magnesium · 500 mg

Dimagnesium malate supplies a well-absorbed mineral relevant to vascular tone, heart rhythm, and cellular energy. The 500 mg elemental amount is substantial but higher than the preferred routine supplemental range.

Malate gives the focused formula better systemic potential than magnesium oxide. The high amount may cause diarrhea or abdominal cramping, and the product does not cover lipids, nitric oxide, or other major cardiovascular pathways.

Study evidence
Magnesium Supportive 158 studies
Sleep Support
Sleep Support
Impact
High effect
B Goal FitB Strength of SupportC CoverageA Formula Quality
Magnesium · 500 mg

Magnesium supports muscle and nervous-system relaxation, making it relevant when low intake contributes to poor sleep. Dimagnesium malate is well absorbed, though the formula does not directly regulate circadian timing.

The 500 mg elemental serving is higher than many sleep-focused magnesium doses and requires four tablets. It may cause loose stools or abdominal discomfort in sensitive users despite the useful organic form.

Study evidence
Magnesium Supportive 23 studies
Stress Relief
Stress Relief
Impact
High effect
B Goal FitB- Strength of SupportC- CoverageA- Formula Quality
Magnesium · 500 mg

Magnesium supports nervous system regulation, but the malate form is often chosen more for general cellular energy than calming. The single mineral does not add adaptogenic or direct neurotransmitter support.

The amount is clearly disclosed and uses a well-absorbed form, though it sits above common supplemental use. The high amount may cause digestive upset, while the streamlined formula avoids unrelated actives.

Study evidence
Magnesium Supportive 13 studies
Testosterone Support
Testosterone Support
Impact
High effect
C+ Goal FitB+ Strength of SupportD+ CoverageA+ Formula Quality
Magnesium · 500 mg

Dimagnesium malate may support endocrine function when magnesium status is low. Evidence for raising testosterone is limited outside deficiency or intense physical training.

The 500 mg amount is clearly disclosed in a well-absorbed form but sits above the usual supplemental target. The full serving may cause diarrhea or cramping and requires extra caution with impaired kidney function.

Study evidence
Magnesium Disputed 5 studies
General Health
General Health
Impact
High effect
A- Goal FitB- Strength of SupportD CoverageA- Formula Quality
Magnesium · 500 mg

Dimagnesium malate is a well-absorbed form that supports muscle, nerve, and cellular-energy functions. The elemental amount is clearly stated and paired with malic acid from the same compound.

The 500 mg serving is above the usual supplemental target and may be harder to tolerate, especially across four tablets. A lower daily amount may better suit routine use for people prone to loose stools or stomach discomfort.

Study evidence
Magnesium Supportive 114 studies

Ingredients

IngredientAmount per serving
Magnesium (DiMagnesium Malate)
 500 mg
Malic Acid (DiMagnesium Malate)
 1436 mg
Gluten Free Adults 18–50 Vegan Vegetarian
Report overview
Magnesium (DiMagnesium Malate) · 500 mg OverallScore69
B- Active Ingredient Quality & BioavailabilityB Dose, Safety & Label TransparencyD+ Value

Dimagnesium malate is a well-absorbed form with a clearly stated elemental magnesium amount. The serving sits above the preferred therapeutic range and may be harder on the stomach for sensitive users. Value is limited by the above-median cost and lack of a disclosed patented raw material, while the four-tablet serving may also be inconvenient.

View ingredientView products
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88 Performance

Magnesium Bisglycinate Powder

NOW
<p>Magnesium bisglycinate supplies a well-absorbed form at a practical, moderate amount. Compared with the original, its magnesium form, dose clarity, and focused design offer a stronger quality-oriented option.</p>
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Cal/Mag 500 mg/250 mg

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<p>Chelated calcium and magnesium provide a focused, balanced mineral formula with strong form quality. Compared with the original, its magnesium form, dose clarity, and focused design offer a stronger quality-oriented option.</p>
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Magnesium Bisglycinate 200 mg

Natural Factors
<p>A focused magnesium bisglycinate powder uses a highly absorbable form at a moderate, practical amount. Compared with the original, its magnesium form, dose clarity, and focused design offer a stronger quality-oriented option.</p>
85 Budget

Magnesium Bisglycinate Chelate

Healthy Origins
<p>TRAACS magnesium bisglycinate provides high-quality absorption quality, a useful elemental amount, and strong serving value in a clean powder. Its lower supplied serving cost makes it a more economical magnesium option than the original.</p>
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Krebs Magnesium Potassium Complex

Nature's Way
<p>Magnesium lysinate and malate provide favorable forms at a useful amount, with a modest potassium contribution. Its lower supplied serving cost makes it a more economical magnesium option than the original.</p>
83 Budget

Magnesium Citrate Pure Powder

Best Naturals
<p>A well-aligned amount of magnesium citrate delivers useful absorption in a focused powder. Its lower supplied serving cost makes it a more economical magnesium option than the original.</p>
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Magnesium Glycinate

NOW
<p>Magnesium glycinate is a well-absorbed form that is often gentle on digestion. Its stated magnesium form, practical dose, and lower serving cost offer a stronger balance of quality and value than the original.</p>
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Magnesium Citrate 420 mg

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<p>A substantial amount of magnesium citrate offers useful absorption and a focused formula. Its stated magnesium form, practical dose, and lower serving cost offer a stronger balance of quality and value than the original.</p>
83 Value

Magnesium Citrate 200 mg

Best Naturals
<p>A substantial amount of magnesium citrate combines useful absorption with a focused single-active design. Its stated magnesium form, practical dose, and lower serving cost offer a stronger balance of quality and value than the original.</p>
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Sources

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

  1. Magnesium status and magnesium therapy in critically ill patients: A systematic review.
    Fairley J; Glassford NJ; Zhang L; Bellomo R · Journal of critical care · 2016
    Systematic review34 studies pooledGeneral Health forMagnesium
  2. Hospital-Acquired Dysmagnesemia and In-Hospital Mortality.
    Cheungpasitporn W; Thongprayoon C; Chewcharat A; Petnak T; Mao MA; Davis PW; Bathini T; Vallabhajosyula S; Qureshi F; Erickson SB · Medical sciences (Basel, Switzerland) · 2024
    Cohort study26,020 participantsGeneral Health forMagnesium
  3. 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
  4. 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
  5. 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
  6. The association between circulating magnesium and clinically relevant outcomes in patients with chronic kidney disease: A systematic review and meta-analysis.
    Leenders NHJ; Vermeulen EA; van Ballegooijen AJ; Hoekstra T; de Vries R; Beulens JW; Vervloet MG · Clinical nutrition (Edinburgh, Scotland) · 2021
    Meta-analysis348,059 participants33 studies pooledGeneral Health forMagnesium
  7. 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 pooledGeneral Health Cardiovascular Support forMagnesium
  8. Magpie Trial in the UK: methods and additional data for women and children at 2 years following pregnancy complicated by pre-eclampsia.
    Smyth RM; Spark P; Armstrong N; Duley L · BMC pregnancy and childbirth · 2009
    Randomized trial1,601 participantsGeneral Health forMagnesium
  9. 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
  10. Effects of oral magnesium therapy on exercise tolerance, exercise-induced chest pain, and quality of life in patients with coronary artery disease.
    Shechter M; Bairey Merz CN; Stuehlinger HG; Slany J; Pachinger O; Rabinowitz B · The American journal of cardiology · 2003
    Randomized trial187 participantsGeneral 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. 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
  21. 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
  22. Red blood cell magnesium and chronic fatigue syndrome.
    Cox IM; Campbell MJ; Dowson D · Lancet (London, England) · 1991
    Randomized trial32 participantsEnergy forMagnesium
  23. Exercise, magnesium and immune function.
    Laires MJ; Monteiro C · Magnesium research · 2008
    Narrative reviewEnergy forMagnesium
  24. 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
  25. 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
  26. 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
  27. 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
  28. Effects of magnesium and potassium supplementation on insomnia and sleep hormones in patients with diabetes mellitus.
    Khalid S; Bashir S; Mehboob R; Anwar T; Ali M; Hashim M; Waseem H; Basharat S · Frontiers in endocrinology · 2024
    Randomized trial320 participantsSleep Support forMagnesium
  29. Association of magnesium intake with sleep duration and sleep quality: findings from the CARDIA study.
    Zhang Y; Chen C; Lu L; Knutson KL; Carnethon MR; Fly AD; Luo J; Haas DM; Shikany JM; Kahe K · Sleep · 2022
    Cohort study3,964 participantsSleep Support forMagnesium
  30. Lidocaine vs. magnesium: effect on analgesia after a laparoscopic cholecystectomy.
    Saadawy IM; Kaki AM; Abd El Latif AA; Abd-Elmaksoud AM; Tolba OM · Acta anaesthesiologica Scandinavica · 2010
    Randomized trial120 participantsSleep Support forMagnesium
  31. The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial.
    Abbasi B; Kimiagar M; Sadeghniiat K; Shirazi MM; Hedayati M; Rashidkhani B · Journal of research in medical sciences : the official journal of Isfahan University of Medical Sciences · 2013
    Randomized trial46 participantsSleep Support forMagnesium
  32. A randomized, double-blind, placebo-controlled, multicenter study assessing the efficacy of magnesium oxide monohydrate in the treatment of nocturnal leg cramps.
    Barna O; Lohoida P; Holovchenko Y; Bazylevych A; Velychko V; Hovbakh I; Bula L; Shechter M · Nutrition journal · 2021
    Randomized trial175 participantsSleep Support forMagnesium
  33. 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
  34. 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
  35. 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
  36. 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
  37. 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
  38. 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
  39. 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
  40. 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
  41. 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
  42. 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