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B12 500 mcg

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4.7
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(775 ratings)
Vitamin B12 500 mcg
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Score83
A straightforward 500 mcg cyanocobalamin tablet with a large supply. It is practical, though less specialized than active-form B12 products.
How scoring works
Quantity:200 Tablet(s) • (200 servings)
Goals:
General Health
Energy
Productivity Boost
Hair Health

Score 83

A straightforward 500 mcg cyanocobalamin tablet with a large supply. It is practical, though less specialized than active-form B12 products.
How scoring works

Also available as

1 option
1000.00mcg • 120 Tablet(s) servings 1000.00mcg • 120 Tablet(s) • 120 servings $7.06 ($0.05 per serving)
$8.77($0.04 per serving)
Amazon
$ 19.90
iHerb
$ 8.77
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Analysis

Cyanocobalamin provides stable B12 for normal blood-cell production, nerve function, and energy metabolism. A 500 mcg amount is lower than many megadose products while still offering substantial supplementation.

The single-active tablet and large count make routine use simple. No folate, B6, or other nutrient broadens the formula, so its benefit depends on B12 being the relevant gap.

Cyanocobalamin must be converted to active coenzyme forms, but it remains a practical option for many users. People seeking an active-form product may prefer methylcobalamin or hydroxocobalamin.

Who is it for
  • Adults seeking basic B12 support
  • People with low animal-food intake
  • Users who want a large tablet supply
Best for
  • Routine B12 supplementation
  • Supporting normal energy metabolism
  • Simple single-nutrient use

Pros

  • Moderate relative to megadose products
  • Stable cyanocobalamin form
  • Large serving count

Cons

  • Requires conversion to active forms
  • Still exceeds normal daily requirements
  • No complementary nutrients

Nutrient quality

82 Highest impact

The vitamin form provides only limited bioavailability confidence. The amount is meaningful without a major safety imbalance.

Ingredient transparency

85 Highest impact

Active amounts are clearly disclosed and no proprietary blend is shown. Inactive ingredients and full daily-use directions are missing from the supplied data.

Customer satisfaction

68 High impact

The average rating is strong, with a moderate evidence base behind it. No specific feedback is supplied to judge repeated complaints or whether experience matches the intended use.

Value for money

97 Highest impact

The supply provides strong cost efficiency for the active amount. A focused formula avoids unnecessary nutrient extras.

Report analysis

Goals

General Health
General Health
Impact
High effect
A Goal FitB Strength of SupportC- CoverageA- Formula Quality
Vitamin B12 · 500 mcg

Vitamin B12 is an essential nutrient for red blood cell formation, nerve function, and energy metabolism. The 500 mcg amount is useful for maintenance or modestly increased needs, with clear label disclosure.

Cyanocobalamin is stable and well studied but is less directly bioactive than methylcobalamin or adenosylcobalamin. The simple tablet provides focused deficiency support rather than broad general-health coverage.

Study evidence
Vitamin B12 Adverse 66 studies
Energy
Energy
Impact
High effect
A- Goal FitC Strength of SupportD CoverageA+ Formula Quality
Vitamin B12 · 500 mcg

Vitamin B12 is directly involved in normal energy metabolism and red blood cell formation, especially when intake or absorption is inadequate. The 500 mcg amount is useful, but cyanocobalamin and a swallowed tablet are less optimized than a bioactive mucosal format.

The formula is narrowly focused and clearly labeled rather than a broad energy solution. People with adequate B12 status should not expect a stimulant-like effect from taking more B12.

Study evidence
Vitamin B12 Disputed 14 studies
Productivity Boost
Productivity Boost
Impact
Moderate effect
C- Goal FitB- Strength of SupportD- CoverageA Formula Quality
Vitamin B12 · 500 mcgVitamin B12 · 500 mcg

Vitamin B12 may reduce fatigue and restore mental stamina when low B12 status is the cause. The 500 mcg amount is clearly disclosed but is unlikely to increase productivity in users with adequate status.

Cyanocobalamin provides a standard swallowed tablet with limited absorption advantages. The single-vitamin design does not address acute alertness, stress resilience, or broader cognitive pathways.

Study evidence
Vitamin B12 Supportive 15 studies
Vitamin B12 No effect 17 studies
Hair Health
Hair Health
Impact
Moderate effect
F Goal FitB+ Strength of SupportF CoverageA Formula Quality

Vitamin B12 may support hair growth when deficiency is affecting cell turnover or blood formation. A 500 mcg standalone serving is unlikely to improve hair in someone with adequate B12.

The simple label is transparent but uses cyanocobalamin rather than a bioactive form. Its narrow scope leaves iron, zinc, protein structure, and follicle signaling unaddressed.

Study evidence
Vitamin B12 Disputed 17 studies

Ingredients

IngredientAmount per serving
Vitamin B12 (Cyanocobalamin)
 500 mcg
Gluten Free Adults 18–50 Dairy Free Sugar Free Vegetarian
Report overview
Vitamin B12 (Cyanocobalamin) · 500 mcg OverallScore62
F Active Ingredient Quality & BioavailabilityB Dose, Safety & Label TransparencyA+ Value

The 500 mcg amount provides moderate potency at an efficient cost. Cyanocobalamin is a less preferred B12 form, and the swallowed tablet does not target mucosal absorption. Clear labeling makes the product easy to assess.

View ingredientView products
Loading alternative details
89 Performance

Methyl B-12 1000 mcg & Methyl Folate 400 mcg plus P-5-P Lemon Flavor

Jarrow Formulas
<p>Methylcobalamin, folate, and active vitamin B6 support linked energy and methylation pathways with clearly stated amounts. Compared with the original 500 mcg cyanocobalamin serving, the bioactive form improves form quality without relying on conversion from cyanocobalamin.</p>
87 Performance

Fully Active B12 1500 mcg

Doctor's Best
<p>1,500 mcg of bioactive methylcobalamin provides a focused, easy-to-assess vitamin B12 option. Compared with the original 500 mcg cyanocobalamin serving, the bioactive form improves form quality without relying on conversion from cyanocobalamin.</p>
87 Performance

B12 Energizer+ Natural Cherry Flavor

Advanced Nutrition by Zahler
<p>5,000 mcg of bioactive methylcobalamin provides a focused, easy-to-assess vitamin B12 option. Compared with the original 500 mcg cyanocobalamin serving, the bioactive form improves form quality without relying on conversion from cyanocobalamin.</p>
86 Budget

Vitamin B12 2000 mcg

Nutricost
<p>One of the lowest-cost eligible options provides 2,000 mcg of methylcobalamin in a clearly disclosed formula. Compared with the original 500 mcg cyanocobalamin serving, the bioactive form improves form quality without relying on conversion from cyanocobalamin.</p>
86 Budget

Quick Dissolve B-12 Methylcobalamin 2500 mcg

Nature's Bounty
<p>One of the lowest-cost eligible options provides 2,500 mcg of methylcobalamin in a clearly disclosed formula. Compared with the original 500 mcg cyanocobalamin serving, the bioactive form improves form quality without relying on conversion from cyanocobalamin.</p>
87 Budget

B12 Methylcobalamin 1000 mcg

Natural Factors
<p>One of the lowest-cost eligible options provides 1,000 mcg of methylcobalamin in a clearly disclosed formula. Compared with the original 500 mcg cyanocobalamin serving, the bioactive form improves form quality without relying on conversion from cyanocobalamin.</p>
87 Value

Chewable Fully Active B12 Chocolate Mint Flavor 1000 mcg

Doctor's Best
<p>1,000 mcg of methylcobalamin supplies a bioactive form without low-value nutrient extras. The focused formula supports reasonable value, and compared with the original 500 mcg cyanocobalamin serving, the bioactive form improves form quality without relying on conversion from cyanocobalamin.</p>
85 Value

Vegan B12 2500 mcg

DEVA
<p>2,500 mcg of methylcobalamin supplies a bioactive form without low-value nutrient extras. The focused formula supports reasonable value, and compared with the original 500 mcg cyanocobalamin serving, the bioactive form improves form quality without relying on conversion from cyanocobalamin.</p>
83 Value

Sublingual Methylcobalamin 1000 mcg

Solgar
<p>1,000 mcg of methylcobalamin supplies a bioactive form without low-value nutrient extras. The focused formula supports reasonable value, and compared with the original 500 mcg cyanocobalamin serving, the bioactive form improves form quality without relying on conversion from cyanocobalamin.</p>
Report alternatives

Sources

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

  1. Cobalamin deficiency: clinical picture and radiological findings.
    Briani C; Dalla Torre C; Citton V; Manara R; Pompanin S; Binotto G; Adami F · Nutrients · 2014
    Narrative reviewEnergy forVitamin B12
  2. Vitamin B12 Supplementation: Is More Always Better?
    Yepes-Calderón M; Doorenbos CSE; Stegmann ME; Touw DJ; Harmsen HJM; Heiner-Fokkema MR; van Spronsen FJ; Corpeleijn E; Bakker SJL · Nutrients · 2026
    Narrative reviewEnergy forVitamin B12
  3. Vitamin B12 Supplementation in Diabetic Neuropathy: A 1-Year, Randomized, Double-Blind, Placebo-Controlled Trial.
    Didangelos T; Karlafti E; Kotzakioulafi E; Margariti E; Giannoulaki P; Batanis G; Tesfaye S; Kantartzis K · Nutrients · 2021
    Randomized trial90 participantsGeneral Health forVitamin B12
  4. Relationship between serum B12 concentrations and mortality: experience in NHANES.
    Wolffenbuttel BHR; Heiner-Fokkema MR; Green R; Gans ROB · BMC medicine · 2021
    Cohort study24,262 participantsGeneral Health forVitamin B12
  5. A new perspective on vitamin B12 deficiency in rheumatology: a case-based review.
    Dułak NA; Rytlewska M; Jaskólska M; Chmielewski M · Rheumatology international · 2024
    Case series3 participantsEnergy forVitamin B12
  6. Effects of Vitamin B12 Supplementation on Cognitive Function, Depressive Symptoms, and Fatigue: A Systematic Review, Meta-Analysis, and Meta-Regression.
    Markun S; Gravestock I; Jäger L; Rosemann T; Pichierri G; Burgstaller JM · Nutrients · 2021
    Meta-analysis6,276 participants16 studies pooledEnergy forVitamin B12
  7. Patients' experiences with methylcobalamin injections in amyotrophic lateral sclerosis.
    Zubair AS; Saab L; Scharer K; Khokhar B · Brain circulation · 2024
    Qualitative study5 participantsEnergy forVitamin B12
  8. Vitamin B12 Deficiency: Common Questions and Answers.
    Patel H; McGuirk R · American family physician · 2025
    Narrative reviewEnergy forVitamin B12
  9. Oral Vitamin B12 versus Placebo for the Prevention of Chemotherapy-Induced Peripheral Neuropathy in Gynecological Cancer Patients: A Randomized, Double-Blind, Placebo-Controlled Trial.
    Insin P; Chaiwongsa T; Prueksaritanond N · Asian Pacific journal of cancer prevention : APJCP · 2026
    Randomized trial40 participantsGeneral Health forVitamin B12
  10. A single-center randomized controlled trial of local methylcobalamin injection for subacute herpetic neuralgia.
    Xu G; Lv ZW; Feng Y; Tang WZ; Xu GX · Pain medicine (Malden, Mass.) · 2014
    Randomized trial98 participantsGeneral Health forVitamin B12
  11. Local Injection of Methylcobalamin Combined with Lidocaine for Acute Herpetic Neuralgia.
    Xǔ G; Xu S; Tang WZ; Xú G; Cheng C; Xu J · Pain medicine (Malden, Mass.) · 2017
    Randomized trial204 participantsGeneral Health forVitamin B12
  12. The Effect of Vitamin B12 and Folic Acid Supplementation on Serum Homocysteine, Anemia Status and Quality of Life of Patients with Multiple Sclerosis.
    Nozari E; Ghavamzadeh S; Razazian N · Clinical nutrition research · 2022
    Clinical trial50 participantsGeneral Health forVitamin B12
  13. Quantitative Analysis of Selected Circulating Hematological Biomarkers, Essential Minerals, Vitamins, and Thyroid Hormones in Females Affected by Hair Loss.
    Al-Fawaeir S; Al-Odat I · Diseases (Basel, Switzerland) · 2025
    Case-control study200 participantsHair Health forVitamin B12
  14. Factors Associated with Premature Hair Graying in a Young Indian Population.
    Chakrabarty S; Krishnappa PG; Gowda DG; Hiremath J · International journal of trichology · 2016
    Case-control study74 participantsHair Health forVitamin B12
  15. Risk Factors for Pediatric Alopecia Areata: Clinical and Biochemical Findings from a Case - Control Study.
    İritaş SY · Dermatology practical & conceptual · 2026
    Case-control study600 participantsHair Health forVitamin B12
  16. Hair Loss After Laparoscopic Sleeve Gastrectomy.
    Katsogridaki G; Tzovaras G; Sioka E; Perivoliotis K; Zachari E; Magouliotis D; Tasiopoulou V; Chatedaki C; Zacharoulis D · Obesity surgery · 2019
    Cohort study50 participantsHair Health forVitamin B12
  17. Demographic Characteristics and Association of Serum Vitamin B12, Ferritin and Thyroid Function with Premature Canities in Indian Patients from an Urban Skin Clinic of North India: A Retrospective Analysis of 71 Cases.
    Sonthalia S; Priya A; Tobin DJ · Indian journal of dermatology · 2022
    Cross-sectional study71 participantsHair Health forVitamin B12
  18. Effects of Folic Acid and Vitamin B12, Alone and in Combination on Cognitive Function and Inflammatory Factors in the Elderly with Mild Cognitive Impairment: A Single-blind Experimental Design.
    Ma F; Zhou X; Li Q; Zhao J; Song A; An P; Du Y; Xu W; Huang G · Current Alzheimer research · 2020
    Randomized trial240 participantsProductivity Boost forVitamin B12
  19. Effects of Physical Activity and Micronutrients on Cognitive Performance in Children Aged 6 to 11 Years: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
    Meli AM; Ali A; Mhd Jalil AM; Mohd Yusof H; Tan MMC · Medicina (Kaunas, Lithuania) · 2022
    Meta-analysisProductivity Boost forVitamin B12
  20. Cognitive function in an elderly population: interaction between vitamin B12 status, depression, and apolipoprotein E ε4: the Hordaland Homocysteine Study.
    Vogiatzoglou A; Smith AD; Nurk E; Drevon CA; Ueland PM; Vollset SE; Nygaard HA; Engedal K; Tell GS; Refsum H · Psychosomatic medicine · 2013
    Cross-sectional study1,935 participantsProductivity Boost forVitamin B12
  21. Cognitive profile and inflammatory markers in children and adolescents with specific learning disorder: a cross-sectional study.
    Balatacı U; Ay B · Frontiers in pediatrics · 2026
    Case-control study108 participantsProductivity Boost forVitamin B12
  22. Association between vitamin B12 levels and cognitive impairment in older adults.
    Aguilar-Navarro SG; Carbajal-Silva JC; Palacios-Hernández MGI; Gutiérrez-Gutierrez LA; Ávila-Funes JA; Mimenza-Alvarado AJ · Gaceta medica de Mexico · 2023
    Cross-sectional study241 participantsProductivity Boost forVitamin B12
  23. Effects of vitamin B12 on performance and circadian rhythm in normal subjects.
    Mayer G; Kröger M; Meier-Ewert K · Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 1997
    Randomized trial20 participantsProductivity Boost forVitamin B12
  24. Prenatal vitamin B12 status and cognitive functioning in children at 4 years of age: The ECLIPSES Study.
    Cruz-Rodríguez J; Canals-Sans J; Hernández-Martínez C; Voltas-Moreso N; Arija V · Maternal & child nutrition · 2023
    Cohort study249 participantsProductivity Boost forVitamin B12
  25. Dietary intakes and biomarker patterns of folate, vitamin B6, and vitamin B12 can be associated with cognitive impairment by hypermethylation of redox-related genes NUDT15 and TXNRD1.
    An Y; Feng L; Zhang X; Wang Y; Wang Y; Tao L; Qin Z; Xiao R · Clinical epigenetics · 2020
    Cohort study2,533 participantsProductivity Boost forVitamin B12
  26. Homocysteine, folate, and vitamins B6 and B12 blood levels in relation to cognitive performance: the Maine-Syracuse study.
    Elias MF; Robbins MA; Budge MM; Elias PK; Brennan SL; Johnston C; Nagy Z; Bates CJ · Psychosomatic medicine · 2008
    Cross-sectional study812 participantsProductivity Boost forVitamin B12