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C-1000 Complex

4.7
★ ★ ★ ★ ★
(73 ratings)
Vitamin C 1000 mg
Product Image
Score77
A potent, good-value vitamin C capsule with modest plant-based additions. The unbuffered 1,000 mg serving may be more than some users need or tolerate comfortably.
How scoring works
Capsule
Quantity:100 Capsule(s) • (100 servings)
Goals:
Immunity
General Health
Anti-Inflammatory Support
Skin Health

Score 77

A potent, good-value vitamin C capsule with modest plant-based additions. The unbuffered 1,000 mg serving may be more than some users need or tolerate comfortably.
How scoring works
$18.99($0.18 per serving)
iHerb
$ 18.99
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Analysis

The 1,000 mg ascorbic acid serving provides substantial antioxidant and immune support and can contribute to collagen formation. Citrus bioflavonoids and rose hips complement the main ingredient, but their amounts are small relative to vitamin C.

Capsule delivery avoids the sugar and tooth exposure associated with gummies or chewables. Plain ascorbic acid offers no stated buffering or enhanced absorption feature, so tolerance is the central formulation trade-off.

The active amount offers favorable value for users who specifically want a full-strength serving. People seeking gentler dosing or broader nutrient coverage may prefer a lower-dose buffered formula.

Who is it for
  • Adults seeking a high-potency vitamin C capsule
  • Users who want modest bioflavonoid support
  • People avoiding gummy carbohydrates
Best for
  • Immune support
  • Antioxidant support
  • Collagen support

Pros

  • Clearly stated 1,000 mg serving
  • Includes citrus bioflavonoids
  • Good active-ingredient value

Cons

  • Unbuffered ascorbic acid
  • Supporting plant ingredients are modestly dosed
  • No enhanced delivery system is disclosed

Warnings

  • A full 1,000 mg serving may cause nausea or loose stools in sensitive users.
  • Unbuffered ascorbic acid may aggravate acid-sensitive stomachs.
  • The fixed high serving offers less flexibility for people who prefer smaller divided amounts.

Nutrient quality

79 High impact

Ascorbic acid is conventional, while citrus bioflavonoids provide a modest supporting matrix. The substantial vitamin C serving is sufficient for focused supplementation.

Ingredient transparency

81 Highest impact

All listed active amounts are disclosed without a proprietary blend. Complete directions and inactive-ingredient details remain incomplete.

Customer satisfaction

67 High impact

The aggregate rating and its volume provide a favorable top-level signal. Missing experience details prevent assessment of repeated complaints or purpose-specific satisfaction.

Value for money

79 High impact

The substantial core dose supports good value despite modest supporting ingredients. Incomplete additive detail limits a stronger conclusion.

Report analysis

Goals

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

A high vitamin C amount directly supports antioxidant defense and normal immune-cell function. Citrus bioflavonoids and rose hips add a related but modest layer of plant compounds.

Plain ascorbic acid remains unbuffered and may be less comfortable for sensitive stomachs. The formula has strong depth for vitamin C but limited breadth across immune pathways.

Study evidence
Vitamin C Supportive 53 studies
General Health
General Health
Impact
Highest effect
A- Goal FitB+ Strength of SupportC CoverageA- Formula Quality
Vitamin C · 1000 mg

A high vitamin C amount supports antioxidant defenses, immune function, and collagen formation. Bioflavonoids and rose hips add modest complementary plant compounds.

The active amounts are clearly disclosed and the vitamin C serving is substantial. Unbuffered ascorbic acid may be less comfortable for acid-sensitive users.

Study evidence
Vitamin C Supportive 56 studies
Anti-Inflammatory Support
Cellular Defense
Anti-Inflammatory Support
Impact
High effect
C+ Goal FitB Strength of SupportC- CoverageB+ Formula Quality
Vitamin C · 1000 mg

A high vitamin C amount supports antioxidant defenses, while citrus bioflavonoids provide a smaller complementary contribution. The rose hip amount is too small to add much practical depth.

The formula remains more antioxidant-focused than directly anti-inflammatory. Its core pairing is logical, although the token rose hip addition slightly weakens the streamlined design.

Study evidence
Vitamin C Supportive 50 studies
Skin Health
Skin Health
Impact
High effect
C Goal FitB+ Strength of SupportD CoverageB Formula Quality
Vitamin C · 1000 mg

A high vitamin C amount supports collagen synthesis and antioxidant defenses. Hesperidin and rose hips provide secondary antioxidant context without addressing hydration or the skin barrier.

Amounts are disclosed, although the supporting botanicals are modest. The focused design offers strong cofactor depth rather than broad skin-pathway coverage.

Study evidence
Vitamin C Supportive 53 studies
Vision Support
Macular and Blue Light Defense
Vision Support
Impact
Moderate effect
D Goal FitC Strength of SupportD+ CoverageB Formula Quality
Vitamin C · 1000 mg

Vitamin C offers only a limited connection to focused eye health. Some relevant amounts are useful, while others are better suited to general antioxidant support.

Coverage is concentrated on ocular antioxidant defense. The remaining ascorbic acid may cause digestive discomfort in sensitive users.

Study evidence
Vitamin C Disputed 24 studies

Ingredients

IngredientAmount per serving
Vitamin C (Ascorbic Acid)
 1000 mg
Citrus Bioflavonoid extract (Hesperidin)
 55 mg
Rose Hips
5 mg
Gluten Free Adults 18–50 Dairy Free
Report overview
Vitamin C (Ascorbic Acid) · 1000 mg OverallScore64
F Active Ingredient Quality & BioavailabilityA Dose, Safety & Label TransparencyB+ Value

The 1,000 mg amount reaches the top of the preferred range and includes modest citrus bioflavonoids and rose hips. Unbuffered ascorbic acid lacks enhanced delivery and may be harder on sensitive stomachs. Vitamin C cost efficiency remains favorable despite the supporting ingredients.

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. Vitamin C supplementation in kidney failure: effect on uraemic symptoms.
    Singer RF · Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association · 2011
    Randomized trial99 participantsGeneral Health forVitamin C
  4. 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
  5. 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
  6. 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
  7. 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
  8. 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
  9. Vitamin C and postoperative outcomes following mandibular third molar extraction: a randomized split-mouth study.
    Demirel M; Aktas A; Kizil M; Yalcin N · Oral surgery, oral medicine, oral pathology and oral radiology · 2026
    Randomized trial56 participantsSkin Health forVitamin C
  10. 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
  11. 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
  12. 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
  13. 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
  14. 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
  15. 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
  16. 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
  17. 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
  18. 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
  19. 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
  20. 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
  21. 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
  22. 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
  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. 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
  29. Nutritional modulation of cataract.
    Weikel KA; Garber C; Baburins A; Taylor A · Nutrition reviews · 2014
    Narrative reviewVision Support forVitamin C
  30. 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
  31. 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