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Pure Buffered Calcium Ascorbate

NOW
4.7
★ ★ ★ ★ ★
(1401 ratings)
Vitamin C 890 mg
Product Image
Score89
A clear, economical buffered vitamin C powder with strong dose transparency and flexible use.
How scoring works
Quantity:8 Liquid(s) • (203 servings)
Goals:
General Health
Immunity
Skin Health
Anti-Inflammatory Support
Vision Support

Score 89

A clear, economical buffered vitamin C powder with strong dose transparency and flexible use.
How scoring works
$7.50($0.03 per serving)
Daily Vita
$ 11.00
Walmart
$ 15.47
Pure Formulas
$ 11.32
iHerb
$ 11.63
Daily Vita
$ 7.50
Vitacost
$ 12.79
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Analysis

Calcium ascorbate supplies a substantial vitamin C amount in a buffered form that may suit people who find plain ascorbic acid uncomfortable. The separate calcium amount makes the mineral contribution easy to understand.

The powder format allows flexible mixing and avoids a long list of supporting actives. Clear quantities and a minimal formula make it easier to assess than products with overlapping ingredient entries.

Its main limitation is narrow coverage: vitamin C supports several normal functions but does not replace a broader nutrient formula. Supplied directions are incomplete, so users should measure the powder according to the current package.

Who is it for
  • People who prefer vitamin C powder
  • Users sensitive to acidic ascorbic acid
  • Adults wanting an adjustable serving
Best for
  • Buffered vitamin C supplementation
  • Flexible dose measurement
  • Minimal-ingredient routines

Pros

  • Uses buffered calcium ascorbate
  • Separately discloses vitamin C and calcium
  • Minimal formula with strong practical value

Cons

  • Requires measuring rather than taking a ready-made capsule
  • Use directions are not included in the supplied data
  • Provides only one main nutrient pathway

Warnings

  • Measure the powder using the current package directions because the supplied data do not include full use instructions.
  • The serving contributes calcium, which should be included when tracking total calcium intake.

Nutrient quality

93 Highest impact

The buffered mineral ascorbate form and the disclosed dose provide meaningful vitamin C support. The focused formula avoids major active padding.

Ingredient transparency

91 Highest impact

Active amounts and ingredient names are clearly disclosed. Daily directions and a complete inactive-ingredient list are not supplied.

Customer satisfaction

70 High impact

The supplied rating is strong and rests on moderate review volume. Detailed feedback themes are absent, leaving repeated complaints and purpose fit uncertain.

Value for money

97 Highest impact

The meaningful vitamin C dose offers favorable value relative to the serving cost. The formula is competitive without relying heavily on low-value extras.

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Goals

General Health
General Health
Impact
Highest effect
A- Goal FitA+ Strength of SupportC CoverageA+ Formula Quality
Vitamin C · 890 mg

Buffered calcium ascorbate delivers a substantial vitamin C amount in a simple, clearly disclosed formula. The form may be gentler on the stomach than plain ascorbic acid.

The product offers strong depth for antioxidant, collagen, and immune-related support but remains a single-nutrient approach. The added calcium amount is transparent and does not obscure the main vitamin C contribution.

Study evidence
Vitamin C Supportive 56 studies
Immunity
Immunity
Impact
Highest effect
A Goal FitA+ Strength of SupportC- CoverageA+ Formula Quality
Vitamin C · 890 mg

Vitamin C directly supports immune-cell function, barrier defenses, and antioxidant protection. Buffered calcium ascorbate supplies a meaningful amount with strong digestive-comfort and disclosure qualities.

Separate vitamin C and calcium amounts make the active contribution unusually clear. The focused formula has strong depth but covers only one major immune nutrient pathway.

Study evidence
Vitamin C Supportive 53 studies
Skin Health
Skin Health
Impact
High effect
B- Goal FitA Strength of SupportC CoverageB+ Formula Quality
Vitamin C · 890 mg

Buffered vitamin C supplies a substantial amount needed for normal collagen synthesis and antioxidant defense. The disclosed mineral ascorbate form may be gentler on the stomach than plain ascorbic acid.

The focused formula provides strong depth for one nutrient but does not supply collagen, ceramides, or direct hydration support. Supporting bioflavonoids add antioxidant context without making the product comprehensive.

Study evidence
Vitamin C Supportive 53 studies
Anti-Inflammatory Support
Anti-Inflammatory Support
Impact
High effect
B- Goal FitA- Strength of SupportC- CoverageA Formula Quality
Vitamin C · 890 mg

A substantial vitamin C serving supports antioxidant defenses and helps limit oxidative stress linked with inflammatory activity. Calcium ascorbate is buffered, which may improve comfort for people sensitive to acidic vitamin C.

The powder has a clear active amount and a straightforward formulation. Its focused design provides depth in antioxidant support but does not cover direct inflammatory enzymes or several complementary pathways.

Study evidence
Vitamin C Supportive 50 studies
Vision Support
Vision Support
Impact
High effect
B Goal FitA- Strength of SupportD- CoverageA+ Formula Quality
Vitamin C · 890 mg

Vitamin C supplies a well-established ocular antioxidant and is part of clinically studied eye-nutrient combinations. Used alone, it cannot reproduce the broader protection of a complete AREDS2-style formula.

Buffered calcium ascorbate is clearly disclosed and may be gentler than plain ascorbic acid. The focused antioxidant design does not provide macular pigments, omega-3 fats, or zinc for broader eye support.

Study evidence
Vitamin C Disputed 24 studies

Ingredients

IngredientAmount per serving
Vitamin C (Calcium Ascorbate)
 890 mg
Calcium (Calcium Ascorbate)
 100 mg
Gluten Free Adults 18–50 Vegan Dairy Free Vegetarian
Report overview
Vitamin C (Calcium Ascorbate) · 890 mg OverallScore93
B+ Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyA+ Value

Buffered calcium ascorbate offers a stomach-friendly form with an efficient 890 mg vitamin C serving. Separate vitamin C and calcium amounts make the mineral contribution unusually clear. A minimal formula and very low cost per gram add strong practical value.

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Loading alternative details
89 Performance

C-500 Calcium Ascorbate-C

NOW
The clearly disclosed vitamin C form provides a more focused alternative to the original buffered vitamin C 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 clearly disclosed vitamin C form provides a more focused alternative to the original buffered vitamin C 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 clearly disclosed vitamin C form provides a more focused alternative to the original buffered vitamin C 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 buffered vitamin C 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 does not show a clear saving, but this is among the closest low-cost candidates available. Compared with the original buffered vitamin C 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 does not show a clear saving, but this is among the closest low-cost candidates available. Compared with the original buffered vitamin C 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 buffered vitamin C 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 buffered vitamin C 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 buffered vitamin C formula. Its 1,100 mg of sodium ascorbate is fully buffered, but the disclosed 120 mg of sodium matters for sodium-restricted users.
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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. 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
  5. 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
  6. 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
  7. 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
  8. 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
  9. 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
  10. 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
  11. 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
  12. 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
  13. 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
  14. 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
  15. 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
  16. 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
  17. 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
  18. 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
  19. 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
  20. 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
  21. 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
  22. 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
  23. 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
  24. 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
  25. Nutritional modulation of cataract.
    Weikel KA; Garber C; Baburins A; Taylor A · Nutrition reviews · 2014
    Narrative reviewVision Support forVitamin C
  26. 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
  27. 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