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Timed Release Vitamin C 500 mg

4.8
★ ★ ★ ★ ★
(431 ratings)
Vitamin C 500 mg
Product Image
Score82
A good-value 500 mg timed-release vitamin C capsule with a simple formula. It remains unbuffered, and the practical benefit of the release system is not quantified.
How scoring works
Capsule
Quantity:90 Capsule(s) • (90 servings)
Goals:
Immunity
General Health
Skin Health
Anti-Inflammatory Support
Vision Support

Score 82

A good-value 500 mg timed-release vitamin C capsule with a simple formula. It remains unbuffered, and the practical benefit of the release system is not quantified.
How scoring works
$6.86($0.07 per serving)
iHerb
$ 6.86
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Analysis

The capsule provides 500 mg of vitamin C, a practical amount for antioxidant, immune, and collagen-related support. Timed release may spread delivery over a longer period, although no release profile is provided.

The formula is simple and economical, which suits users who do not want extra ingredients. Because the active is still unbuffered ascorbic acid, extended release should not be assumed to solve stomach sensitivity.

It is a reasonable middle-dose option for consistent use. Users seeking fully buffered vitamin C or broader vision, skin, and inflammatory support will find the formula limited.

Who is it for
  • Adults wanting a moderate vitamin C capsule
  • Users who prefer timed-release formats
  • Value-conscious buyers
Best for
  • Steady daily vitamin C use
  • Antioxidant support
  • Immune support

Pros

  • Practical 500 mg amount
  • Timed-release format
  • Simple active profile
  • Good value

Cons

  • Uses unbuffered ascorbic acid
  • Release profile is not provided
  • No complementary nutrients

Warnings

  • Unbuffered vitamin C may still cause stomach discomfort
  • Do not crush or chew a timed-release capsule unless its label permits it
  • People with recurrent calcium-oxalate kidney stones should discuss regular high-dose use with a clinician

Nutrient quality

89 Highest impact

The dose is meaningful and the timed-release design adds a useful delivery feature. Unbuffered ascorbic acid still offers limited stomach-comfort support.

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Ingredient transparency

84 Highest impact

Active names and amounts are clearly stated, with no hidden proprietary dose. Complete intake directions and a full inactive-ingredient list are not included in the supplied data.

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Customer satisfaction

70 High impact

Supplied satisfaction metrics indicate a strong result with a meaningful response pool. Detailed experience themes are absent, so recurring complaints and real-world purpose fit remain uncertain.

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Value for money

82 Highest impact

Serving value appears favorable relative to the disclosed form and amount. The focused formula avoids low-value extras.

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Report analysis

Goals

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

A useful vitamin C serving directly supports immune-cell function and antioxidant protection. Timed release may spread delivery across the day.

The active is ordinary unbuffered ascorbic acid, so the delivery design may not improve stomach comfort. Its narrow formula provides strong depth for one immune pathway rather than broad coverage.

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

Vitamin C provides established antioxidant and collagen-related support in a useful 500 mg amount. Timed release may spread delivery, although the active remains unbuffered ascorbic acid.

The focused capsule clearly discloses its active and dose. It addresses one foundational nutrient well but does not provide the breadth of a balanced daily formula.

Study evidence
Vitamin C Supportive 56 studies
Skin Health
Skin Health
Impact
High effect
B- Goal FitB+ Strength of SupportD+ CoverageA+ Formula Quality
Vitamin C · 500 mg

Vitamin C supports collagen synthesis and antioxidant protection at a useful amount. Timed-release ascorbic acid provides a clearly disclosed active, while extended release may spread exposure but does not improve the active form.

Support remains concentrated on collagen cofactors and oxidative defense, with no additional skin pathways. The focused design is easy to understand but cannot provide structural proteins or barrier lipids by itself.

Study evidence
Vitamin C Supportive 53 studies
Anti-Inflammatory Support
Cellular Defense
Anti-Inflammatory Support
Impact
High effect
B- Goal FitB Strength of SupportD- CoverageA+ Formula Quality
Vitamin C · 500 mg

Timed-release ascorbic acid provides direct antioxidant support that may help limit oxidative inflammatory stress. Unbuffered ascorbic acid may be less comfortable for sensitive users and does not add broader pathway coverage.

The disclosed 500 mg amount gives the main antioxidant pathway meaningful depth. The single-ingredient design is focused and avoids unrelated additions..

Study evidence
Vitamin C Supportive 50 studies
Vision Support
Macular and Blue Light Defense
Vision Support
Impact
High effect
C- Goal FitB+ Strength of SupportD- CoverageA Formula Quality
Vitamin C · 500 mg

Timed-release ascorbic acid provides antioxidant support that may help protect ocular tissues from oxidative stress. Vitamin C alone does not supply macular pigments, structural omega-3 fats, or a complete evidence-based vision combination.

The disclosed amount is substantial for antioxidant support. The timed-release capsule is clearly described, although the active remains unbuffered ascorbic acid.

Study evidence
Vitamin C Disputed 24 studies

Ingredients

IngredientAmount per serving
Vitamin C (Ascorbic Acid)
 500 mg
Gluten Free Adults 18–50 Dairy Free Sugar Free
Report overview
Vitamin C (Ascorbic Acid) · 500 mg OverallScore77
C Active Ingredient Quality & BioavailabilityA Dose, Safety & Label TransparencyB+ Value

A timed-release capsule delivers a useful Vitamin C amount over an extended period. The active remains unbuffered ascorbic acid, so sensitive users may not gain much gastric comfort. Cost efficiency is good for a sustained-delivery format.

View ingredientView products
Loading alternative details
89 Performance

C-500 Calcium Ascorbate-C

NOW
The buffered vitamin C form may be easier to tolerate than the original plain ascorbic acid formula. Its 500 mg of calcium ascorbate is buffered and includes 55 mg of calcium; the 10 mg bioflavonoid addition is modest.
88 Performance

Buffered Gold C

California Gold Nutrition
The buffered vitamin C form may be easier to tolerate than the original plain ascorbic acid formula. Its 1,000 mg of sodium ascorbate is buffered and simply formulated, with 130 mg of sodium clearly disclosed.
88 Performance

Sodium Ascorbate Capsules

NutriBiotic Immunity
The buffered vitamin C form may be easier to tolerate than the original plain ascorbic acid formula. Its capsules provide 850 mg of buffered sodium ascorbate with a clearly disclosed 100 mg sodium contribution.
85 Budget

C-500 With Rose Hips

NOW
The supplied serving-cost data indicates a less expensive way to obtain a comparable vitamin C serving. Compared with the original plain ascorbic acid formula, it supplies 500 mg of ascorbic acid with 40 mg of rose hips, although the vitamin C remains unbuffered.
83 Budget

C 500 mg

21st Century
The supplied serving-cost data indicates a less expensive way to obtain a comparable vitamin C serving. Compared with the original plain ascorbic acid formula, it supplies 500 mg of ascorbic acid with 30 mg of calcium in a basic, clearly dosed formula.
85 Budget

Gold C Vitamin C 1000 mg

California Gold Nutrition
The supplied serving-cost data indicates a less expensive way to obtain a comparable vitamin C serving. Compared with the original plain ascorbic acid formula, it supplies 1,000 mg of plain ascorbic acid without extra actives, favoring simplicity rather than buffering.
87 Value

100% Pure Vitamin C Powder

Swanson Premium Brand
The combination of a focused ingredient list and efficient supply makes it a stronger value candidate than the original plain ascorbic acid formula. Its powder provides 1,000 mg of ascorbic acid with flexible measuring, though the acidic form may not suit every user.
87 Value

C 500 mg

Mason Natural
The combination of a focused ingredient list and efficient supply makes it a stronger value candidate than the original plain ascorbic acid formula. Its single active is 500 mg of ascorbic acid, making the label easy to assess despite the lack of buffering.
88 Value

Sodium Ascorbate

NutriBiotic Immunity
The combination of a focused ingredient list and efficient supply makes it a stronger value candidate than the original plain ascorbic acid formula. Its 1,100 mg of sodium ascorbate is fully buffered, but the disclosed 120 mg of sodium matters for sodium-restricted users.
Report alternatives

Sources

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

  1. Mortality in randomized trials of antioxidant supplements for primary and secondary prevention: systematic review and meta-analysis.
    Bjelakovic G; Nikolova D; Gluud LL; Simonetti RG; Gluud C · JAMA · 2007
    Meta-analysis232,606 participants68 studies pooledGeneral Health forVitamin C
  2. Vitamin C intake and multiple health outcomes: an umbrella review of systematic reviews and meta-analyses.
    Xu K; Peng R; Zou Y; Jiang X; Sun Q; Song C · International journal of food sciences and nutrition · 2022
    Meta-analysis76 studies pooledGeneral Health forVitamin C
  3. 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
  4. Effect of Vitamin C Supplements on Respiratory Tract Infections: A Systematic Review and Meta-Analysis.
    Keya TA; Leela A; Fernandez K; Habib N; Rashid M · Current reviews in clinical and experimental pharmacology · 2022
    Meta-analysis10 studies pooledImmunity forVitamin C
  5. 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
  6. The effect of macronutrient and micronutrient supplements on COVID-19: an umbrella review.
    SeyedAlinaghi S; Shahidi R; Mojdeganlou H; Akhtaran FK; Maroufi SF; Maroufi SP; Mirzapour P; Karimi A; Khodaei S; Pour MM; Mehraeen E; Dadras O · Journal of health, population, and nutrition · 2024
    Systematic review28 studies pooledImmunity forVitamin C
  7. Double-blind, half-face study comparing topical vitamin C and vehicle for rejuvenation of photodamage.
    Fitzpatrick RE; Rostan EF · Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.] · 2002
    Non-randomized trial10 participantsSkin Health forVitamin C
  8. 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
  9. Comparison of the Efficacy of Intralesional Ascorbic Acid Mesotherapy and Intralesional Tranexamic Acid in Treating Melasma in the Skin of Colour Population.
    Aslam H; Muhammad A; Ullah A; Aziz N; Lakhiar JA; Ahmad B; Shahzadi A; Ahmad A; Chandni; Virdi G · Cureus · 2025
    Randomized trial110 participantsSkin Health forVitamin C
  10. Antioxidant vitamin and mineral supplements for preventing age-related macular degeneration.
    Evans JR; Lawrenson JG · The Cochrane database of systematic reviews · 2018
    Meta-analysis55,614 participants4 studies pooledVision Support forVitamin C
  11. What did we learn in 35 years of research on nutrition and supplements for age-related macular degeneration: a systematic review.
    Pameijer EM; Heus P; Damen JAA; Spijker R; Hooft L; Ringens PJ; Imhof SM; van Leeuwen R · Acta ophthalmologica · 2023
    Systematic review27 studies pooledVision Support forVitamin C
  12. 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
  13. Effects of vitamin C on oxidative stress, inflammation, muscle soreness, and strength following acute exercise: meta-analyses of randomized clinical trials.
    Righi NC; Schuch FB; De Nardi AT; Pippi CM; de Almeida Righi G; Puntel GO; da Silva AMV; Signori LU · European journal of nutrition · 2021
    Meta-analysis313 participants18 studies pooledAnti-Inflammatory Support forVitamin C
  14. Vitamin C supplementation and C-reactive protein levels: Findings from a systematic review and meta-analysis of clinical trials.
    Safabakhsh M; Emami MR; Zeinali Khosroshahi M; Asbaghi O; Khodayari S; Khorshidi M; Alizadeh S; Viri EH · Journal of complementary & integrative medicine · 2024
    Meta-analysis818 participants11 studies pooledAnti-Inflammatory Support forVitamin C
  15. A High Vitamin C Micronutrient Supplement Is Unable to Attenuate Inflammation in People with Metabolic Syndrome but May Improve Metabolic Health Indices: A Randomised Controlled Trial.
    Vlasiuk E; Zawari M; Whitehead R; Williman J; Carr AC · Antioxidants (Basel, Switzerland) · 2024
    Randomized trial72 participantsAnti-Inflammatory Support forVitamin C
  16. 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
  17. 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
  18. 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
  19. 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
  20. 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
  21. 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
  22. 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
  23. 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
  24. 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
  25. 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
  26. 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
  27. 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
  28. 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
  29. 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
  30. 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
  31. 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
  32. 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
  33. 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
  34. Nutritional modulation of cataract.
    Weikel KA; Garber C; Baburins A; Taylor A · Nutrition reviews · 2014
    Narrative reviewVision Support forVitamin C
  35. 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
  36. 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