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Double Strength Iron 36 mg

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Iron 36 mg
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Score85
The chelated form combines strong absorption potential with better digestive tolerance than many standard iron salts. The formula has no vitamin C, folate, or vitamin B12 and is too strong for casual use.
How scoring works
Quantity:90 Capsule(s) • (90 servings)
Goals:
Hair Health
Fitness
Energy
Productivity Boost
Immunity

Score 85

The chelated form combines strong absorption potential with better digestive tolerance than many standard iron salts. The formula has no vitamin C, folate, or vitamin B12 and is too strong for casual use.
How scoring works

Also available as

1 option
18.00mg • 120 servings Iron 18 mg • 120 Capsule(s) • 120 servings $4.50 ($0.03 per serving)
$9.22($0.10 per serving)
iHerb
$ 9.78
Daily Vita
$ 9.30
Pure Formulas
$ 9.22
iHerb
$ 9.78
Vitacost
$ 10.53
Walmart
$ 12.39
Amazon
$ 9.29
Report prices

Analysis

Ferrochel iron bisglycinate supplies 36 mg of iron in one capsule. The chelated form combines strong absorption potential with better digestive tolerance than many standard iron salts.

A high amount can support energy, hair, fitness, and immune goals when laboratory results show iron is low. Very low serving cost makes this an economical premium chelate.

The formula has no vitamin C, folate, or vitamin B12 and is too strong for casual use. Iron status and the reason for supplementation should guide duration and dose.

Who is it for
  • Adults with confirmed iron deficiency
  • Budget-focused users seeking a chelated form
  • People needing a high-potency single capsule
Best for
  • Clinician-guided iron repletion
  • Cost-efficient bisglycinate
  • People sensitive to ferrous sulfate

Pros

  • Highly absorbable Ferrochel form
  • Clearly stated 36 mg amount
  • One-capsule convenience
  • Very low serving cost

Cons

  • High amount needs a clear reason for use
  • No absorption cofactor
  • No blood-cell-supporting B vitamins

Warnings

  • The 36 mg serving may cause nausea, constipation, or abdominal discomfort.
  • Use iron for a confirmed need; unnecessary intake can accumulate, particularly in people with hemochromatosis or other iron-overload conditions.
  • Iron can reduce absorption of levothyroxine and some tetracycline or quinolone antibiotics, so separate doses as directed by a pharmacist.
  • Keep iron supplements away from children because accidental ingestion can cause serious iron poisoning.

Nutrient quality

85 Highest impact

Premium bisglycinate and a high amount create strong deficiency-focused potency. The amount raises clear overload, digestive, and accidental-ingestion concerns.

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Ingredient transparency

84 Highest impact

The iron form and amount are specific, with no hidden blend. Intake directions and non-active ingredients were not included in the supplied details.

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Customer satisfaction

73 High impact

The available satisfaction metric is favorable and the sample provides useful confidence. Specific experience details are absent, so repeated complaints and purpose fit remain uncertain.

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Value for money

96 Highest impact

Strong active quality and a very low serving cost provide excellent value. The focused formula is competitive without relying on weak extras.

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Report analysis

Goals

Hair Health
Hair Health
Impact
Highest effect
A- Goal FitA+ Strength of SupportD+ CoverageA- Formula Quality
Iron · 36 mg

36 mg of Ferrochel iron bisglycinate may meaningfully reduce shedding when low iron stores are the cause. Iron has strong relevance for confirmed deficiency, but it does not broadly address hair loss from other causes.

The chelated form is well absorbed and clearly disclosed in a convenient single capsule. Iron should not be used casually when stores are adequate because excess iron can cause digestive effects and is unsafe for people with iron-overload disorders.

Study evidence
Iron Disputed 25 studies
Fitness
Fitness
Impact
Highest effect
A- Goal FitA+ Strength of SupportD CoverageA+ Formula Quality

Iron can preserve endurance and work capacity when low status limits hemoglobin and oxygen delivery. The disclosed amount uses a highly absorbable bisglycinate form in a convenient capsule.

Iron does not improve fitness performance in athletes with adequate status and can be harmful when unnecessary. The capsules must be stored securely because accidental iron ingestion can cause severe poisoning in children.

Study evidence
Iron Supportive 81 studies
Energy
Energy
Impact
Highest effect
A Goal FitB Strength of SupportD+ CoverageA+ Formula Quality
Iron · 36 mg

Iron bisglycinate supports oxygen transport and can improve energy when iron deficiency is present. The chelated form and clearly disclosed amount are strong product-level features.

The amount is high for routine use without confirmed need and approaches the adult upper intake level. Excess iron can cause digestive effects and poses overload risk for people who are not deficient.

Study evidence
Iron Supportive 74 studies
Productivity Boost
Productivity Boost
Impact
High effect
B- Goal FitA Strength of SupportD+ CoverageA+ Formula Quality
Iron · 36 mg

Iron can improve energy and mental clarity when low iron status is causing fatigue, but it is not a general productivity enhancer. Evidence is strong for correcting deficiency and weak for use in people whose iron status is already adequate.

The bisglycinate chelate is well absorbed and the amount is appropriate for targeted supplementation. Unnecessary iron can accumulate or cause digestive effects, so regular use should be guided by a demonstrated need.

Study evidence
Iron Supportive 69 studies
Immunity
Immunity
Impact
High effect
D Goal FitB+ Strength of SupportD CoverageA+ Formula Quality

Iron can support immune-cell growth when deficiency is confirmed, but routine supplementation is not a broad immune strategy. The bisglycinate chelate is well absorbed and precisely disclosed.

The high iron amount is intended for targeted repletion rather than casual seasonal use. People without confirmed deficiency could face digestive effects or excess iron, which may also impair immune balance.

Study evidence
Iron Supportive 23 studies

Ingredients

IngredientAmount per serving
Iron (Ferrochel Iron Bisglycinate)
 36 mg
Gluten Free Adults 18–50 Vegan Dairy Free Vegetarian
Report overview
Iron (Ferrochel Iron Bisglycinate) · 36 mg OverallScore91
B Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyA+ Value

Ferrochel iron bisglycinate offers a gentle, highly absorbable form at an effective 36 mg dose. One capsule is convenient, although the formula lacks vitamin C and supportive B vitamins. Very low serving cost makes the premium chelate especially economical.

View ingredientView products
Loading alternative details
85 Performance

Iron Complex

Advanced Nutrition by Zahler
Ferrochel iron is paired with vitamin C, methylcobalamin, folic acid, and histidine, giving broader disclosed support for energy and hair goals. Its iron amount is lower than the original’s 36 mg. The added nutrients make it less minimal than a single-ingredient iron product.
87 Performance

Vegan True Iron Support

Source Naturals
Ferrochel bisglycinate iron is combined with vitamin C, folic acid, and vitamin B12, with strong iron and energy alignment. Its iron amount is lower than the original’s 36 mg. Cyanocobalamin and folic acid are clearly listed, although other forms may be preferred by some users.
86 Performance

Chelated Iron 18 mg

Bluebonnet
The concise formula uses a clearly identified ferrous bisglycinate chelate and avoids unrelated active ingredients. Its iron amount is lower than the original’s 36 mg. The simpler amount may suit users who do not need a higher-dose or multi-ingredient formula.
77 Budget

Iron 65 mg

Nature Made
The lower serving cost provides a clearly identified ferrous sulfate form. Its iron amount is higher than the original’s 36 mg. The single-active formula keeps the formula similarly focused on iron.
85 Budget

Iron 25 mg

Source Naturals
The lower serving cost provides iron as an explicitly named amino acid chelate. Its iron amount is lower than the original’s 36 mg. The single-active formula keeps the formula similarly focused on iron.
85 Budget

Iron Ferrochel Ferrous Bisglycinate Chelate 36 mg

California Gold Nutrition
The lower serving cost provides iron as a clearly identified Ferrochel ferrous bisglycinate chelate. Its iron amount stays close to the original’s 36 mg. The single-active formula keeps the formula similarly focused on iron.
86 Value

High Absorption Iron with Ferrochel 27 mg

Doctor's Best
The lower serving cost provides a focused Ferrochel iron formula with favorable iron and hair-goal alignment. Its iron amount is lower than the original’s 36 mg. The single-active formula keeps the formula similarly focused on iron.
80 Value

Iron 27 mg

21st Century
The lower serving cost provides ferrous gluconate iron with a disclosed calcium amount. Its iron amount is lower than the original’s 36 mg. The added calcium makes it less minimal than a single-ingredient iron option.
78 Value

Prenatal Multivitamin/Multimineral with Folate

Spring Valley
The lower serving cost provides iron alongside folate, vitamin C, vitamin D3, zinc, and other prenatal nutrients. Its iron amount stays close to the original’s 36 mg. The iron form is not supplied, and the prenatal focus may be unnecessary for someone seeking iron alone.
Report alternatives

Sources

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

  1. The role of iron homeostasis in remodeling immune function and regulating inflammatory disease.
    Mu Q; Chen L; Gao X; Shen S; Sheng W; Min J; Wang F · Science bulletin · 2023
    Narrative reviewImmunity forIron
  2. Lack of Evidence on Association between Iron Deficiency and COVID-19 Vaccine-Induced Neutralizing Humoral Immunity.
    Faizo AA; Bawazir AA; Almashjary MN; Hassan AM; Qashqari FS; Barefah AS; El-Kafrawy SA; Alandijany TA; Azhar EI · Vaccines · 2023
    Case-control study130 participantsImmunity forIron
  3. The Benefits and Risks of Iron Supplementation in Pregnancy and Childhood.
    Georgieff MK; Krebs NF; Cusick SE · Annual review of nutrition · 2020
    Narrative reviewImmunity forIron
  4. The Effect of Parenteral or Oral Iron Supplementation on Fatigue, Sleep, Quality of Life and Restless Legs Syndrome in Iron-Deficient Blood Donors: A Secondary Analysis of the IronWoMan RCT.
    Macher S; Herster C; Holter M; Moritz M; Matzhold EM; Stojakovic T; Pieber TR; Schlenke P; Drexler C; Amrein K · Nutrients · 2021
    Randomized trial176 participantsEnergy forIron
  5. Clinical evaluation of iron treatment efficiency among non-anemic but iron-deficient female blood donors: a randomized controlled trial.
    Waldvogel S; Pedrazzini B; Vaucher P; Bize R; Cornuz J; Tissot JD; Favrat B · BMC medicine · 2012
    Randomized trial154 participantsEnergy forIron
  6. Intravenous iron for the treatment of fatigue in nonanemic, premenopausal women with low serum ferritin concentration.
    Krayenbuehl PA; Battegay E; Breymann C; Furrer J; Schulthess G · Blood · 2011
    Randomized trial90 participantsEnergy forIron
  7. Effects of Oral Iron Supplementation on Blood Iron Status in Athletes: A Systematic Review, Meta-Analysis and Meta-Regression of Randomized Controlled Trials.
    Šmid AN; Golja P; Hadžić V; Abazović E; Drole K; Paravlic AH · Sports medicine (Auckland, N.Z.) · 2024
    Meta-analysis449 participants13 studies pooledFitness forIron
  8. Marginal iron deficiency without anemia impairs aerobic adaptation among previously untrained women.
    Brownlie T; Utermohlen V; Hinton PS; Giordano C; Haas JD · The American journal of clinical nutrition · 2002
    Randomized trial41 participantsFitness forIron
  9. Effect of Intravenous Iron on Aerobic Capacity and Iron Metabolism in Elite Athletes.
    Burden RJ; Pollock N; Whyte GP; Richards T; Moore B; Busbridge M; Srai SK; Otto J; Pedlar CR · Medicine and science in sports and exercise · 2016
    Randomized trial15 participantsFitness forIron
  10. Iron status in diffuse telogen hair loss among women.
    Moeinvaziri M; Mansoori P; Holakooee K; Safaee Naraghi Z; Abbasi A · Acta dermatovenerologica Croatica : ADC · 2010
    Case-control study60 participantsHair Health forIron
  11. Scientific Opinion on the substantiation of a health claim related to iron and maintenance of normal hair growth pursuant to Article 13(5) of Regulation (EC) No 1924/2006.
    EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) · EFSA journal. European Food Safety Authority · 2026
    Guideline / consensusHair Health forIron
  12. Large-dose intravenous ferric carboxymaltose injection for iron deficiency anemia in heavy uterine bleeding: a randomized, controlled trial.
    Van Wyck DB; Mangione A; Morrison J; Hadley PE; Jehle JA; Goodnough LT · Transfusion · 2010
    Randomized trial477 participantsEnergy forIron
  13. Ferric carboxymaltose vs. oral iron in the treatment of pregnant women with iron deficiency anemia: an international, open-label, randomized controlled trial (FER-ASAP).
    Breymann C; Milman N; Mezzacasa A; Bernard R; Dudenhausen J; FER-ASAP investigators · Journal of perinatal medicine · 2018
    Randomized trial252 participantsEnergy forIron
  14. Effect of iron therapy on fatigue symptoms in non-anaemic iron deficient women of reproductive age- A Randomized Controlled Trial.
    Sultana N; Bajwa FA; Sikandar MZ; Haider MM; Majeed T · JPMA. The Journal of the Pakistan Medical Association · 2026
    Randomized trial164 participantsEnergy forIron
  15. Intravenous iron isomaltoside treatment of women suffering from severe fatigue after postpartum hemorrhage.
    Holm C; Thomsen LL; Langhoff-Roos J · The journal of maternal-fetal & neonatal medicine : the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians · 2019
    Randomized trial85 participantsEnergy forIron
  16. Ferric carboxymaltose in patients with heart failure and iron deficiency.
    Anker SD; Comin Colet J; Filippatos G; Willenheimer R; Dickstein K; Drexler H; Lüscher TF; Bart B; Banasiak W; Niegowska J; Kirwan BA; Mori C; von Eisenhart Rothe B; Pocock SJ; Poole-Wilson PA; Ponikowski P; FAIR-HF Trial Investigators · The New England journal of medicine · 2010
    Randomized trial459 participantsFitness forIron
  17. Ferric Carboxymaltose Versus Ferrous Fumarate in Anemic Children with Inflammatory Bowel Disease: The POPEYE Randomized Controlled Clinical Trial.
    Bevers N; Van de Vijver E; Aliu A; Rezazadeh Ardabili A; Rosias P; Stapelbroek J; Bertrams Maartens IA; van de Feen C; Escher H; Oudshoorn A; Teklenburg S; Vande Velde S; Winkens B; Raijmakers M; Vreugdenhil A; Pierik MJ; van Rheenen PF · The Journal of pediatrics · 2023
    Randomized trial64 participantsFitness forIron
  18. Daily iron supplementation for improving anaemia, iron status and health in menstruating women.
    Low MS; Speedy J; Styles CE; De-Regil LM; Pasricha SR · The Cochrane database of systematic reviews · 2016
    Meta-analysis8,506 participants67 studies pooledFitness Productivity Boost forIron
  19. Altered metabolic response of iron-depleted nonanemic women during a 15-km time trial.
    Zhu YI; Haas JD · Journal of applied physiology (Bethesda, Md. : 1985) · 1998
    Randomized trial37 participantsFitness forIron
  20. The Association Between Alopecia Areata and Iron Deficiency Anemia: A Large-Scale Population-Based Case-Control Study.
    Davidovici B; Drutin Y; Ben-Tov A; Mimouni D; Wohl Y · Journal of personalized medicine · 2026
    Case-control study100,203 participantsHair Health forIron
  21. Iron Deficiency and Nonscarring Alopecia in Women: Systematic Review and Meta-Analysis.
    Treister-Goltzman Y; Yarza S; Peleg R · Skin appendage disorders · 2022
    Meta-analysis10,029 participants36 studies pooledHair Health forIron
  22. Comparative Analysis of Postoperative Hair Loss and Micronutrient Deficiencies After One-Anastomosis Gastric Bypass Versus Sleeve Gastrectomy.
    Chinisaz F; Maleki T; Najjari K; Miratashi Yazdi SA · Obesity surgery · 2026
    Cohort study261 participantsHair Health forIron
  23. Assessment of Serum Ferritin Levels in Female Patients With Telogen Effluvium.
    Thamotharan N; Harikumar MV; Sundaram M; Swaminathan A; Rangarajan S · Cureus · 2026
    Cross-sectional study100 participantsHair Health forIron
  24. Diagnosis and treatment of female alopecia: Focusing on the iron deficiency-related alopecia.
    Lin CS; Chan LY; Wang JH; Chang CH · Tzu chi medical journal · 2023
    Cohort study155 participantsHair Health forIron
  25. The immune response in iron-deficient children: Impaired cellular defense mechanisms with altered humoral components.
    Macdougall LG; Anderson R; McNab GM; Katz J · The Journal of pediatrics · 1975
    Single-arm trial27 participantsImmunity forIron
  26. Hepcidin--a peptide hormone at the interface of innate immunity and iron metabolism.
    Ganz T · Current topics in microbiology and immunology · 2006
    Narrative reviewImmunity forIron
  27. Adaptive immunity and vaccination - iron in the spotlight.
    Preston AE; Drakesmith H; Frost JN · Immunotherapy advances · 2025
    Narrative reviewImmunity forIron
  28. Buried Treasure: Evolutionary Perspectives on Microbial Iron Piracy.
    Barber MF; Elde NC · Trends in genetics : TIG · 2016
    Narrative reviewImmunity forIron
  29. Effects of daily iron supplementation in primary-school-aged children: systematic review and meta-analysis of randomized controlled trials.
    Low M; Farrell A; Biggs BA; Pasricha SR · CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne · 2014
    Meta-analysis7,089 participants32 studies pooledProductivity Boost forIron
  30. Consumption of Iron-Biofortified Beans Positively Affects Cognitive Performance in 18- to 27-Year-Old Rwandan Female College Students in an 18-Week Randomized Controlled Efficacy Trial.
    Murray-Kolb LE; Wenger MJ; Scott SP; Rhoten SE; Lung'aho MG; Haas JD · The Journal of nutrition · 2017
    Randomized trial150 participantsProductivity Boost forIron
  31. Functional consequences of iron supplementation in iron-deficient female cotton mill workers in Beijing, China.
    Li R; Chen X; Yan H; Deurenberg P; Garby L; Hautvast JG · The American journal of clinical nutrition · 1994
    Randomized trial80 participantsProductivity Boost forIron
  32. The Effect of Iron-Fortified Lentils on Blood and Cognitive Status among Adolescent Girls in Bangladesh.
    Barnett AL; Wenger MJ; Yunus FM; Jalal C; DellaValle DM · Nutrients · 2023
    Randomized trial359 participantsProductivity Boost forIron