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Ester-C Plus 500 mg Vitamin C

4.9
★ ★ ★ ★ ★
(204 ratings)
Vitamin C 500 mg
Flavonoid (mixture) 200 mg
Product Image
Score85
A focused, buffered daily vitamin C capsule balances comfort, transparency, and value, with only moderate potency per capsule.
How scoring works
Capsule
Quantity:90 Capsule(s) • (90 servings)
Goals:
Immunity
General Health
Anti-Inflammatory Support
Skin Health

Score 85

A focused, buffered daily vitamin C capsule balances comfort, transparency, and value, with only moderate potency per capsule.
How scoring works
$13.27($0.14 per serving)
iHerb
$ 0.00
Daily Vita
$ 13.27
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Analysis

Ester-C provides a buffered calcium ascorbate form with good expected stomach comfort. The moderate amount is easy to fit into a daily routine and may be easier to adjust than a very high-dose product.

Elemental calcium is separately disclosed, and citrus bioflavonoids add a useful companion amount. The formula stays focused without introducing unrelated botanicals or opaque blends.

A single capsule makes routine use convenient, and the supply offers favorable value for a branded buffered form. People specifically wanting a larger vitamin C amount would need multiple capsules, which reduces that convenience.

Who is it for
  • Adults seeking moderate daily vitamin C
  • People with a sensitive stomach
  • Users who want a focused Ester-C formula
Best for
  • Everyday vitamin C use
  • Collagen and skin support
  • Routine immune support

Pros

  • Buffered Ester-C form
  • Calcium amount is disclosed
  • Useful citrus bioflavonoid amount
  • Single-capsule serving

Cons

  • Moderate rather than high potency
  • Multiple capsules are needed for a full-gram amount
  • Bioflavonoid composition is not further characterized

Nutrient quality

88 Highest impact

Ester-C provides a buffered and generally well-tolerated vitamin C form. A moderate vitamin C amount is paired with a useful bioflavonoid dose.

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Ingredient transparency

84 Highest impact

Every listed active has a specific amount. A complete excipient list is not available in the provided data.

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Customer satisfaction

75 High impact

The average rating is very strong. The rating volume is adequate for a useful satisfaction signal.

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Value for money

93 Highest impact

The serving value is competitive for a buffered capsule. The focused formula avoids unnecessary extras.

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Goals

Immunity
Immunity
Impact
Highest effect
A Goal FitA Strength of SupportC+ CoverageA Formula Quality
Vitamin C · 500 mg

A useful vitamin C amount directly supports antioxidant defenses and immune-cell function. Branded, buffered calcium ascorbate should be gentler on the stomach than plain ascorbic acid.

Citrus bioflavonoids add modest complementary antioxidant support without obscuring the main active. The formula remains narrow and does not cover vitamin D, zinc, selenium, or other major immune pathways.

Study evidence
Vitamin C Supportive 53 studies
General Health
General Health
Impact
Highest effect
A- Goal FitA Strength of SupportC CoverageA- Formula Quality
Vitamin C · 500 mg

Buffered Ester-C provides a useful daily vitamin C amount for antioxidant, immune, and collagen support. Calcium ascorbate and citrus bioflavonoids make the formula more considered than plain ascorbic acid alone.

The product still addresses a limited slice of general health rather than broad nutritional coverage. It suits people seeking focused vitamin C support, especially when stomach comfort matters.

Study evidence
Vitamin C Supportive 56 studies
Anti-Inflammatory Support
Cellular Defense
Anti-Inflammatory Support
Impact
High effect
B- Goal FitA- Strength of SupportC+ CoverageA Formula Quality
Vitamin C · 500 mg

Ester-C provides useful antioxidant support in a buffered form suited to routine use. Citrus bioflavonoids add modest complementary antioxidant activity.

The vitamin C and elemental calcium amounts are clearly disclosed, which supports confidence in the formula. Its main limitation is narrow coverage rather than weak dose or form.

Study evidence
Vitamin C Supportive 50 studies
Skin Health
Skin Health
Impact
High effect
B- Goal FitB+ Strength of SupportC- CoverageA- Formula Quality
Vitamin C · 500 mg

Buffered vitamin C and citrus bioflavonoids support collagen synthesis and antioxidant defense. Vitamin C has established skin relevance, while bioflavonoids provide plausible complementary antioxidant support.

The vitamin C amount is meaningful and the bioflavonoid complex is clearly quantified. The formula covers collagen-cofactor and antioxidant pathways but not hydration or direct structure.

Study evidence
Vitamin C Supportive 53 studies
Vision Support
Macular and Blue Light Defense
Vision Support
Impact
Moderate effect
D- Goal FitB+ Strength of SupportD- CoverageB+ Formula Quality
Vitamin C · 500 mg

Vitamin C contributes antioxidant support to ocular tissues but lacks macular carotenoids, DHA, and a vision-specific mineral framework. Evidence supports adequate vitamin C within broader eye-nutrient combinations, not vitamin C alone as a comprehensive vision supplement.

The vitamin C amount is useful for general antioxidant support without adding another direct ocular active. The formula uses vitamin C in a logical antioxidant role.

Study evidence
Vitamin C Disputed 24 studies

Ingredients

IngredientAmount per serving
Vitamin C (Ester-C)
 500 mg
Calcium (Ester-C Calcium Ascorbate)
 55 mg
Citrus Bioflavonoids Complex
200 mg
Gluten Free Adults 18–50 Dairy Free Sugar Free
Report overview
Vitamin C (Ester-C) · 500 mg OverallScore90
A- Active Ingredient Quality & BioavailabilityA- Dose, Safety & Label TransparencyA+ Value

Ester-C provides a branded, pH-neutral calcium ascorbate form with good expected gastric comfort. The useful vitamin C amount and elemental calcium contribution are both clearly disclosed. Low cost per gram makes the premium form excellent value, with bioflavonoids adding modest complementary support.

View ingredientView products
Loading alternative details
89 Performance

C-500 Calcium Ascorbate-C

NOW
<p>The ingredient profile makes it a stronger quality-focused alternative for the same vitamin C goals. Buffered calcium ascorbate delivers a practical vitamin C amount with clear mineral disclosure and exceptional relative value. The small bioflavonoid addition is unlikely to contribute much but does not undermine the strong core formula.</p>
86 Performance

C

Swanson
<p>The ingredient profile makes it a stronger quality-focused alternative for the same vitamin C goals. Fully buffered calcium ascorbate provides a meaningful vitamin C serving with good stomach-comfort potential. The focused formula keeps the active nutrient clear and avoids decorative additions.</p>
87 Performance

Ester-C with Citrus Bioflavonoids

American Health
<p>The ingredient profile makes it a stronger quality-focused alternative for the same vitamin C goals. A buffered vitamin C form and a substantial citrus bioflavonoid amount create a simple, well-dosed antioxidant formula. Strong satisfaction signals and a long supply support value, though excipients and intake directions are not shown.</p>
89 Budget

Pure Buffered Calcium Ascorbate

NOW
<p>The lower serving cost makes it a more economical alternative while retaining the same vitamin C focus. the buffered mineral ascorbate form supplies a meaningful vitamin C amount with a digestive-comfort advantage over plain ascorbic acid. Clear active dosing and favorable serving value are strengths, though complete use directions and inactive ingredients are not supplied.</p>
87 Budget

100% Pure Vitamin C Powder

Swanson Premium Brand
<p>The lower serving cost makes it a more economical alternative while retaining the same vitamin C focus. The pure powder supplies a flexible, meaningful vitamin C serving with exceptional economy and no active padding. Plain ascorbic acid remains acidic, so sensitive users may prefer a buffered form.</p>
87 Budget

C 500 mg

Mason Natural
<p>The lower serving cost makes it a more economical alternative while retaining the same vitamin C focus. A simple moderate-dose tablet provides useful vitamin C at excellent relative value and with extensive aggregate feedback. Generic ascorbic acid and missing inactive-ingredient details are the main limitations.</p>
87 Value

Pure Buffered Magnesium Ascorbate

NOW
<p>The formula offers a more favorable balance of vitamin C quality and serving value than the original. Magnesium ascorbate provides a substantial fully buffered vitamin C serving with excellent relative value and clear mineral disclosure. Feedback volume is limited, and detailed use directions or non-active ingredients are not supplied.</p>
83 Value

C 500 mg

21st Century
<p>The formula offers a more favorable balance of vitamin C quality and serving value than the original. A large supply of straightforward vitamin C provides meaningful daily support with excellent value. Basic ascorbic acid and incomplete inactive-ingredient details keep the formula from feeling premium.</p>
84 Value

Ester-C 500 mg With Citrus Bioflavoinds

American Health
<p>The formula offers a more favorable balance of vitamin C quality and serving value than the original. Buffered Ester-C provides a substantial vitamin C serving with good stomach-comfort potential. Citrus bioflavonoids add compatible plant compounds without distracting from the core nutrient.</p>
Report alternatives

Sources

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

  1. Efficacy of Vitamin C as Glucocorticoid Substitute for Reducing Pain and Inflammation After Total Hip Arthroplasty: A Randomized Controlled Trial.
    Jiang W; Xu H; Jiang X; Zhan Y; Ju Y; Xie J; Huang Z; Huang Q; Pei F · The Journal of bone and joint surgery. American volume · 2025
    Randomized trial107 participantsAnti-Inflammatory Support forVitamin C
  2. The Impact of Vitamin C on Analgesic, Anti-inflammatory, and Hemostatic Outcomes After Total Hip and Knee Arthroplasty: A Systematic Review and Meta-Analysis.
    Moftakhari Hajimirzaei S; Bagherzadeh Cham M; Dolikhani M; Tabatabaee SM; Ebrahimpour A · The archives of bone and joint surgery · 2026
    Meta-analysis1,162 participants10 studies pooledAnti-Inflammatory Support forVitamin C
  3. The impact of vitamin C supplementation on the perioperative outcomes after total hip and knee arthroplasty: a systematic review and meta-analysis.
    Liu X; Guo J; Li Y; Yang Y; Liu M; Gao Q; Yang Y; Wu X; Yue C · BMC musculoskeletal disorders · 2026
    Meta-analysis852 participants8 studies pooledAnti-Inflammatory Support forVitamin C
  4. Therapeutic Impact of Ascorbic Acid on Oral and Periodontal Tissues: A Systematic Literature Review.
    Ruzijevaite G; Acaite E; Jagelaviciene E · Medicina (Kaunas, Lithuania) · 2025
    Systematic review811 participants17 studies pooledAnti-Inflammatory Support forVitamin C
  5. Oral vitamin C administration reduces early recurrence rates after electrical cardioversion of persistent atrial fibrillation and attenuates associated inflammation.
    Korantzopoulos P; Kolettis TM; Kountouris E; Dimitroula V; Karanikis P; Pappa E; Siogas K; Goudevenos JA · International journal of cardiology · 2005
    Randomized trial44 participantsAnti-Inflammatory Support forVitamin C
  6. Dietary intake and blood concentrations of antioxidants and the risk of cardiovascular disease, total cancer, and all-cause mortality: a systematic review and dose-response meta-analysis of prospective studies.
    Aune D; Keum N; Giovannucci E; Fadnes LT; Boffetta P; Greenwood DC; Tonstad S; Vatten LJ; Riboli E; Norat T · The American journal of clinical nutrition · 2019
    Meta-analysis69 studies pooledGeneral Health forVitamin C
  7. Scientific Opinion on the substantiation of a health claim related to vitamin C and increasing non haem iron absorption pursuant to Article 14 of Regulation (EC) No 1924/2006.
    EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) · EFSA journal. European Food Safety Authority · 2026
    Guideline / consensusGeneral Health forVitamin C
  8. Vitamin C Depletion and All-Cause Mortality in Renal Transplant Recipients.
    Sotomayor CG; Eisenga MF; Gomes Neto AW; Ozyilmaz A; Gans ROB; Jong WHA; Zelle DM; Berger SP; Gaillard CAJM; Navis GJ; Bakker SJ · Nutrients · 2018
    Cohort study598 participantsGeneral Health forVitamin C
  9. Associations of Serum Biomarkers of Fruit and Vegetable Intake With the Risk of Cause-Specific Mortality and All-Cause Mortality: A National Prospective Cohort Study.
    Pu L; Zhang R; Wang X; Zhao T; Sun H; Han L · Frontiers in nutrition · 2022
    Cohort study12,530 participantsGeneral Health forVitamin C
  10. Relation between plasma ascorbic acid and mortality in men and women in EPIC-Norfolk prospective study: a prospective population study. European Prospective Investigation into Cancer and Nutrition.
    Khaw KT; Bingham S; Welch A; Luben R; Wareham N; Oakes S; Day N · Lancet (London, England) · 2001
    Cohort study19,496 participantsGeneral Health forVitamin C
  11. Vitamin C and contribution to the normal function of the immune system: evaluation of a health claim pursuant to Article 14 of Regulation (EC) No 1924/2006.
    EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) · EFSA journal. European Food Safety Authority · 2026
    Guideline / consensusImmunity forVitamin C
  12. Therapeutic effects of high-dose vitamin C supplementation in patients with COVID-19: a meta-analysis.
    Sun L; Zhao JH; Fan WY; Feng B; Liu WW; Chen RQ; Ban C; Dang AG; Wang M; Luo KT; Zhou GY; Yu FF; Ba Y · Nutrition reviews · 2024
    Meta-analysis2,334 participants14 studies pooledImmunity forVitamin C
  13. Effect of micronutrient supplements on influenza and other respiratory tract infections among adults: a systematic review and meta-analysis.
    Abioye AI; Bromage S; Fawzi W · BMJ global health · 2021
    Meta-analysisImmunity forVitamin C
  14. New evidence for antioxidant properties of vitamin C.
    Vojdani A; Bazargan M; Vojdani E; Wright J · Cancer detection and prevention · 2001
    Randomized trial20 participantsImmunity forVitamin C
  15. Enhanced Vitamin C Delivery: A Systematic Literature Review Assessing the Efficacy and Safety of Alternative Supplement Forms in Healthy Adults.
    Calder PC; Kreider RB; McKay DL · Nutrients · 2025
    Systematic review13 studies pooledImmunity forVitamin C
  16. Evaluation of the anti-wrinkle effect of an ascorbic acid-loaded dissolving microneedle patch via a double-blind, placebo-controlled clinical study.
    Lee C; Yang H; Kim S; Kim M; Kang H; Kim N; An S; Koh J; Jung H · International journal of cosmetic science · 2017
    Randomized trial23 participantsSkin Health forVitamin C
  17. Comparative Study on the Outcome of Periorbital Wrinkles Treated with Laser-Assisted Delivery of Vitamin C or Vitamin C Plus Growth Factors: A Randomized, Double-blind, Clinical Trial.
    Machado BHB; Frame J; Zhang J; Najlah M · Aesthetic plastic surgery · 2021
    Randomized trial149 participantsSkin Health forVitamin C
  18. Randomized trial of topical ascorbic acid in DMSO versus imiquimod for the treatment of basal cell carcinoma.
    Burke B; Bailie JE · Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie · 2022
    Randomized trial25 participantsSkin Health forVitamin C
  19. Vitamin C improves healing of foot ulcers: a randomised, double-blind, placebo-controlled trial.
    Gunton JE; Girgis CM; Lau T; Vicaretti M; Begg L; Flood V · The British journal of nutrition · 2022
    Randomized trial16 participantsSkin Health forVitamin C
  20. Dietary nutrient intakes and skin-aging appearance among middle-aged American women.
    Cosgrove MC; Franco OH; Granger SP; Murray PG; Mayes AE · The American journal of clinical nutrition · 2007
    Cross-sectional study4,025 participantsSkin Health forVitamin C
  21. Role of Oral Vitamin 'C' on Astigmatic Errors in Phacoemulsification.
    Mohan S; Sah K; Khattri M; Ahmad L; Sachan SK · Current eye research · 2021
    Randomized trial400 participantsVision Support forVitamin C
  22. Ascorbic acid metabolites are involved in intraocular pressure control in the general population.
    Hysi PG; Khawaja AP; Menni C; Tamraz B; Wareham N; Khaw KT; Foster PJ; Benet LZ; Spector TD; Hammond CJ · Redox biology · 2019
    Observational studyVision Support forVitamin C
  23. Nutritional modulation of cataract.
    Weikel KA; Garber C; Baburins A; Taylor A · Nutrition reviews · 2014
    Narrative reviewVision Support forVitamin C
  24. Dietary n-3 Fatty Acid, α-Tocopherol, Zinc, vitamin D, vitamin C, and β-carotene are Associated with Age-Related Macular Degeneration in Japan.
    Aoki A; Inoue M; Nguyen E; Obata R; Kadonosono K; Shinkai S; Hashimoto H; Sasaki S; Yanagi Y · Scientific reports · 2017
    Case-control study530 participantsVision Support forVitamin C
  25. Adherence to a Mediterranean diet, lifestyle and age-related macular degeneration: the Coimbra Eye Study - report 3.
    Raimundo M; Mira F; Cachulo MDL; Barreto P; Ribeiro L; Farinha C; Laíns I; Nunes S; Alves D; Figueira J; Merle BM; Delcourt C; Santos L; Silva R · Acta ophthalmologica · 2019
    Case-control study883 participantsVision Support forVitamin C