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C 1000 mg Timed-Released Formula

4.8
★ ★ ★ ★ ★
(375 ratings)
Vitamin C 1000 mg
Product Image
Score83
Strong vitamin C depth with timed-release convenience. The unbuffered form and narrow formula remain important limitations.
How scoring works
Tablet
Quantity:250 Tablet(s) • (250 servings)
Goals:
General Health
Immunity
Skin Health
Vision Support

Score 83

Strong vitamin C depth with timed-release convenience. The unbuffered form and narrow formula remain important limitations.
How scoring works
$24.89($0.09 per serving)
iHerb
$ 24.89
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Analysis

The 1,000 mg serving offers substantial antioxidant, collagen, and immune support. Timed release may distribute the dose over a longer period than an ordinary tablet.

Standard ascorbic acid remains the main active, so the delivery feature does not remove acidity. The concentrated rose-hip extract is clearly separated but too small to broaden the formula much.

The large bottle makes ongoing use convenient for people specifically targeting vitamin C. It is incomplete for vision, skin barrier, or broad immune support because other relevant nutrients are absent.

Who is it for
  • Adults wanting a full-strength timed-release tablet
  • Users focused on vitamin C intake
  • People seeking a large serving supply
Best for
  • Extended vitamin C delivery
  • Antioxidant and collagen support
  • Single-nutrient supplementation

Pros

  • Full 1,000 mg amount
  • Timed-release format
  • Large number of servings
  • Clear separation of active ingredients

Cons

  • Unbuffered ascorbic acid
  • Small rose-hip addition
  • Narrow pathway coverage
  • No evidence supplied for release duration

Warnings

  • The high unbuffered amount may cause stomach upset or loose stools
  • Timed-release tablets should generally not be crushed or chewed
  • People prone to calcium oxalate kidney stones should consider total vitamin C intake

Nutrient quality

87 Highest impact

Timed release may extend delivery, though the active remains ordinary unbuffered ascorbic acid. The serving is below the adult upper limit, though the amount may bother sensitive stomachs.

Ingredient transparency

81 Highest impact

Each listed active ingredient has a specific amount. Complete excipient details and clear daily intake guidance are not supplied.

Customer satisfaction

72 High impact

The supplied aggregate satisfaction metrics are strong and based on meaningful volume. No feedback excerpts or complaint themes are supplied, so experience patterns cannot be verified.

Value for money

91 Highest impact

Serving value appears favorable for the disclosed dose. The focused ingredient profile avoids costly low-value extras.

Report analysis

Goals

General Health
General Health
Impact
Highest effect
A- Goal FitA- Strength of SupportC CoverageA- Formula Quality
Vitamin C · 1000 mg

Vitamin C at 1,000 mg supplies a full target-range antioxidant and collagen-support amount. Timed release may extend delivery, although the active remains ordinary unbuffered ascorbic acid.

The vitamin C amount is clearly separated from the small rose-hip extract. The focused formula offers strong dose depth, but people with sensitive stomachs may tolerate a buffered form better.

Study evidence
Vitamin C Supportive 56 studies
Immunity
Immunity
Impact
Highest effect
B+ Goal FitA- Strength of SupportC- CoverageA Formula Quality
Vitamin C · 1000 mg

Vitamin C directly supports immune-cell function, epithelial barriers, and antioxidant protection, although it covers only one main immune pathway. Vitamin C has strong established nutritional evidence, with the clearest benefit when intake is inadequate or demand is elevated.

The 1000 mg vitamin C serving reaches the configured immune-support range rather than providing a token amount. The full ascorbic acid amount is clearly separated from rose hips, while timed release may spread delivery over time.

Study evidence
Vitamin C Supportive 53 studies
Skin Health
Skin Health
Impact
High effect
B- Goal FitA- Strength of SupportC- CoverageA- Formula Quality
Vitamin C · 1000 mg

Vitamin C directly supports collagen synthesis and antioxidant defense. Timed release adds a practical delivery feature for this focused formula.

The high amount provides strong pathway depth, though unbuffered ascorbic acid may not suit sensitive users. Rose hips are a small related addition, and no barrier or hydration active broadens coverage.

Study evidence
Vitamin C Supportive 53 studies
Vision Support
Macular and Blue Light Defense
Vision Support
Impact
High effect
C- Goal FitB+ Strength of SupportD CoverageA- Formula Quality
Vitamin C · 1000 mg

Vitamin C provides useful antioxidant support for the lens and other ocular tissues. A single antioxidant cannot replace a broader vision formula built around macular carotenoids, zinc, or structural lipids.

The 1,000 mg amount is clearly disclosed and reaches a meaningful supplemental range. Timed release extends delivery, while the underlying ascorbic acid remains unbuffered and the small rose-hip extract adds little separate depth.

Study evidence
Vitamin C Disputed 24 studies
Anti-Inflammatory Support
Cellular Defense
Anti-Inflammatory Support
Impact
Moderate effect
D+ Goal FitB- Strength of SupportD- CoverageA Formula Quality
Vitamin C · 1000 mg

Vitamin C provides a substantial antioxidant dose with modest anti-inflammatory relevance. It remains a narrower approach than direct inflammation-modulating botanicals or omega-3s.

The amount and timed-release positioning support sustained antioxidant exposure. No second mechanism broadens the formula.

Study evidence
Vitamin C Supportive 50 studies

Ingredients

IngredientAmount per serving
Vitamin C (Ascorbic Acid)
 1000 mg
Rose Hips 4:1 extract
25 mg
Adults 18–50
Report overview
Vitamin C (Ascorbic Acid) · 1000 mg OverallScore81
C Active Ingredient Quality & BioavailabilityA Dose, Safety & Label TransparencyA+ Value

A timed-release tablet delivers a full target-range amount, though the active form itself is ordinary ascorbic acid. The 1,000 mg serving falls within the preferred intake range. The vitamin C dose is clearly separated from the rose hip extract, while the product delivers exceptionally low cost per gram with timed release.

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. 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
  2. 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
  3. 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
  4. 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
  5. 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
  6. 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
  7. 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
  8. 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
  9. 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
  10. 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
  11. 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
  12. 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
  13. 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
  14. 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
  15. 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
  16. 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
  17. 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
  18. 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
  19. 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
  20. 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
  21. 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
  22. 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
  23. 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
  24. 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
  25. 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
  26. 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
  27. 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
  28. Nutritional modulation of cataract.
    Weikel KA; Garber C; Baburins A; Taylor A · Nutrition reviews · 2014
    Narrative reviewVision Support forVitamin C
  29. 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
  30. 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