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Buffer-C pH Controlled 500 mg

4.8
★ ★ ★ ★ ★
(506 ratings)
Vitamin C 500 mg
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Score68
Useful vitamin C with partial buffering, but the supporting blend is poorly disclosed. Undosed quercetin and aloe add label complexity without verifiable depth.
How scoring works
Capsule
Quantity:120 Capsule(s) • (120 servings)
Goals:
Immunity
Skin Health
General Health
Anti-Inflammatory Support

Score 68

Useful vitamin C with partial buffering, but the supporting blend is poorly disclosed. Undosed quercetin and aloe add label complexity without verifiable depth.
How scoring works
$12.49($0.10 per serving)
iHerb
$ 23.19
Pure Formulas
$ 23.19
Amazon
$ 12.49
Vitacost
$ 23.19
Vitacost
$ 23.19
iHerb
$ 23.19
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Analysis

The 500 mg vitamin C amount supports antioxidant defenses, collagen synthesis, and normal immune function. Calcium compounds partially control acidity and may improve stomach comfort.

The 275 mg proprietary mineral blend is not fully broken down. Quercetin and aloe lack measurable amounts, so they should not be credited with meaningful additional support.

The capsule fits users who want partly buffered vitamin C but accept incomplete disclosure. A simpler fully buffered product would be easier to assess for ingredient precision.

Who is it for
  • Adults seeking partly buffered vitamin C
  • Users who prefer capsules
  • People comfortable with a proprietary supporting blend
Best for
  • Moderate vitamin C support
  • Reduced acidity compared with plain ascorbic acid
  • Focused collagen and antioxidant support

Pros

  • Practical 500 mg vitamin C amount
  • Partial mineral buffering
  • Calcium sources are named
  • Capsule avoids a sweetened chewable base

Cons

  • Proprietary mineral blend is not fully disclosed
  • Quercetin amount is unavailable
  • Aloe amount is unavailable
  • Added ingredients provide little verifiable breadth

Warnings

  • The hidden mineral breakdown may matter to users tracking calcium or other minerals
  • Quercetin and aloe effects cannot be assessed without stated amounts
  • Partly buffered vitamin C may still cause digestive discomfort in sensitive users

Nutrient quality

81 Highest impact

The pH-controlled mineral system may reduce acidity, but the underlying vitamin C is ordinary ascorbic acid. The vitamin C serving is meaningful without appearing unnecessarily aggressive for most adults.

Ingredient transparency

52 Moderate impact

Vitamin C and calcium amounts are stated, while the supporting blend and minor actives lack individual amounts. 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

70 High impact

Serving value appears reasonable but not exceptional. Added complexity provides limited clear value relative to the core vitamin C.

Report analysis

Goals

Immunity
Immunity
Impact
High effect
B+ Goal FitB+ Strength of SupportC- CoverageA Formula Quality
Vitamin C · 500 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 500 mg vitamin C serving reaches the configured immune-support range rather than providing a token amount. Ascorbic acid is partly buffered with calcium compounds, but the 275 mg proprietary mineral blend is not fully broken down.

Study evidence
Vitamin C Supportive 53 studies
Skin Health
Skin Health
Impact
High effect
B Goal FitB+ Strength of SupportC- CoverageB Formula Quality
Vitamin C · 500 mg

A useful vitamin C amount supports collagen synthesis and antioxidant defense. Partial buffering may improve stomach comfort compared with plain ascorbic acid.

The proprietary mineral blend is not broken down, and the listed quercetin and aloe lack measurable amounts. The formula therefore provides dependable vitamin C support but little verified breadth.

Study evidence
Vitamin C Supportive 53 studies
General Health
General Health
Impact
High effect
B- Goal FitB Strength of SupportC- CoverageC Formula Quality
Vitamin C · 500 mg

A practical vitamin C amount supports antioxidant defenses, immune function, and collagen formation. Partial mineral buffering may improve comfort compared with plain ascorbic acid.

The proprietary mineral blend is not fully broken down, and quercetin and aloe have no meaningful amounts stated. Those disclosure gaps weaken confidence in the added ingredients and make the formula less focused than a simple buffered vitamin C.

Study evidence
Vitamin C Supportive 56 studies
Anti-Inflammatory Support
Cellular Defense
Anti-Inflammatory Support
Impact
High effect
B- Goal FitB Strength of SupportD CoverageB- Formula Quality
Vitamin C · 500 mg

Vitamin C provides direct antioxidant support that may help limit oxidative inflammatory stress. Undosed quercetin and aloe cannot be credited as meaningful anti-inflammatory contributors.

The disclosed vitamin C amount is useful, while the proprietary mineral blend reduces transparency. The formula is mostly coherent but presents broader support than its disclosed active doses establish.

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

Vitamin C provides a meaningful ocular antioxidant pathway. Quercetin may add antioxidant breadth, but its amount is hidden.

The vitamin C amount is useful and partially buffered, while the proprietary mineral blend limits transparency. The formula lacks carotenoids, zinc-copper balance, vitamin E, and structural lipids.

Study evidence
Vitamin C Disputed 24 studies

Ingredients

IngredientAmount per serving
Vitamin C (Ascorbic Acid)
 500 mg
Calcium (Calcium Carbonate, Dicalcium Phosphate)
 50 mg
Proprietary Mineral Blend
275 mg
Quercetin (Sophora japonica linn)
 0 NP
organic Aloe vera
0 NP
Gluten Free Adults 18–50 Kosher Dairy Free Vegetarian
Report overview
Vitamin C (Ascorbic Acid) · 500 mg OverallScore73
C Active Ingredient Quality & BioavailabilityB+ Dose, Safety & Label TransparencyB+ Value

A pH-controlled mineral blend partially buffers ascorbic acid, improving comfort without reaching full source transparency. The 500 mg serving falls within the preferred intake range. Vitamin C is clearly stated, but the proprietary mineral blend is not fully broken down, while the partially buffered formula offers good cost per gram.

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. 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
  2. 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
  3. 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
  4. Supplemental Vitamins and Minerals for Cardiovascular Disease Prevention and Treatment: JACC Focus Seminar.
    Jenkins DJA; Spence JD; Giovannucci EL; Kim YI; Josse RG; Vieth R; Sahye-Pudaruth S; Paquette M; Patel D; Blanco Mejia S; Viguiliouk E; Nishi SK; Kavanagh M; Tsirakis T; Kendall CWC; Pichika SC; Sievenpiper JL · Journal of the American College of Cardiology · 2021
    Meta-analysisGeneral Health forVitamin C
  5. 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
  6. 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
  7. 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
  8. 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
  9. Vitamin C for the management of COVID-19: a systematic review and meta-analysis of randomized controlled trials.
    Abid H; Mushtaq I; Munir ABI; Shakil J; Vinjamuri S; Tadasare N; Kiran F; Muhammad Wali Mirza A; Fatima Khidri F; Shahid A; Ayyan M; Ehsan M; Cheema HA; Alsubari AMA; Sahra S; Siddiqi NI · Annals of medicine and surgery (2012) · 2026
    Meta-analysis9 studies pooledImmunity forVitamin C
  10. Intake of vitamin C, vitamin E, selenium, zinc and polyunsaturated fatty acids and upper respiratory tract infection-a prospective cohort study.
    Raposo SE; Fondell E; Ström P; Bälter O; Bonn SE; Nyrén O; Plymoth A; Bälter K · European journal of clinical nutrition · 2018
    Cohort study1,533 participantsImmunity forVitamin C
  11. Vitamin C supplementation and salivary immune function following exercise-heat stress.
    Carrillo AE; Murphy RJ; Cheung SS · International journal of sports physiology and performance · 2009
    Randomized trial12 participantsImmunity forVitamin C
  12. Immunocompetence and oxidant defense during ascorbate depletion of healthy men.
    Jacob RA; Kelley DS; Pianalto FS; Swendseid ME; Henning SM; Zhang JZ; Ames BN; Fraga CG; Peters JH · The American journal of clinical nutrition · 1992
    Clinical trial8 participantsImmunity forVitamin C
  13. 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
  14. 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
  15. 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
  16. 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
  17. Association between hemoglobin A1c, Vitamin C, and microbiome in diabetic foot ulcers and intact skin: A cross-sectional study.
    Tong KPS; Green SJ; Ortiz J; Wu SC · Health science reports · 2024
    Cross-sectional study42 participantsSkin Health forVitamin C
  18. 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
  19. Efficacy and Safety of tranexamic acid versus vitamin c after microneedling in treatment of melasma: Clinical and Dermoscopic study.
    El Attar Y; Doghaim N; El Far N; El Hedody S; Hawwam SA · Journal of cosmetic dermatology · 2022
    Randomized trial20 participantsSkin Health forVitamin C
  20. 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
  21. 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
  22. 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
  23. 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
  24. 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
  25. 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
  26. 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
  27. 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
  28. 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
  29. 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
  30. 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
  31. 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
  32. 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
  33. 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
  34. 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
  35. 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
  36. 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
  37. Nutritional modulation of cataract.
    Weikel KA; Garber C; Baburins A; Taylor A · Nutrition reviews · 2014
    Narrative reviewVision Support forVitamin C
  38. 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
  39. 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