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Calcium Ascorbate

4.7
★ ★ ★ ★ ★
(554 ratings)
Vitamin C 1760 mg
Product Image
Score83
A transparent, buffered vitamin C powder that is easier to adjust than fixed-dose capsules. The full serving is large and may be better divided.
How scoring works
Powder
Quantity:16 Ounce(s) • (227 servings)
Goals:
Immunity
General Health
Vision Support
Anti-Inflammatory Support
Skin Health

Score 83

A transparent, buffered vitamin C powder that is easier to adjust than fixed-dose capsules. The full serving is large and may be better divided.
How scoring works
$24.73($0.10 per serving)
iHerb
$ 24.74
Vitacost
$ 24.74
Amazon
$ 24.73
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Analysis

Calcium ascorbate provides 1,760 mg of vitamin C in a less acidic mineral form. The buffered powder may suit people who find plain ascorbic acid uncomfortable.

The label separately states 180 mg of calcium, making the mineral contribution easy to include in daily totals. A powder also permits smaller portions, although it requires accurate measuring.

The full serving is high and may exceed the amount many people need at one time. Dividing it can improve practical absorption and may reduce digestive discomfort while preserving the formula's focused role.

Who is it for
  • Adults seeking non-acidic vitamin C
  • People who want an adjustable powder
  • Users who tolerate calcium ascorbate well
Best for
  • Buffered vitamin C support
  • Flexible serving sizes
  • People sensitive to plain ascorbic acid

Pros

  • Less acidic calcium ascorbate form
  • Vitamin C and calcium are separately disclosed
  • Powder permits dose adjustment

Cons

  • Full serving is very large
  • Adds 180 mg calcium
  • Powder requires measuring

Warnings

  • The 1,760 mg vitamin C serving may cause loose stools or stomach discomfort in sensitive users.
  • The 180 mg calcium contribution should be included when managing total calcium intake.

Nutrient quality

82 Highest impact

Calcium ascorbate is a well-regarded buffered form that may improve stomach comfort. The vitamin C amount is clearly meaningful but larger than most people need at one time.

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Ingredient transparency

86 Highest impact

Vitamin C and calcium are each listed with a specific amount. The active formula is simple, though a complete non-active ingredient statement was not supplied.

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Customer satisfaction

67 High impact

The available aggregate rating is strong for this category. No firsthand outcome details were supplied, so alignment with the intended use is uncertain.

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Value for money

95 Highest impact

The buffered form and large supply support strong quality for the serving cost. The product compares well with other buffered vitamin C powders.

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Goals

Immunity
Immunity
Impact
Highest effect
A+ Goal FitA Strength of SupportC+ CoverageA+ Formula Quality
Vitamin C · 1760 mg

Calcium ascorbate supplies a high vitamin C amount in a buffered form that may be gentler than plain ascorbic acid. Separate vitamin C and calcium disclosure makes the active contribution clear.

Immune depth is strong for antioxidant support, but the product does not cover other major immune pathways. The large vitamin C serving may still cause loose stools and is less absorption-efficient than a moderate divided intake.

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 · 1760 mg

Calcium ascorbate provides a substantial vitamin C amount in a buffered form that may be easier on the stomach. Separate disclosure of vitamin C and calcium makes the formula transparent.

Its general-health contribution is focused, and the serving exceeds the most efficient range for a single dose. Sensitive users may still prefer a smaller divided amount despite the lower-acidity form.

Study evidence
Vitamin C Supportive 56 studies
Vision Support
Vision Support
Impact
High effect
B Goal FitB+ Strength of SupportD+ CoverageA Formula Quality
Vitamin C · 1760 mg

Vitamin C provides relevant antioxidant support for the lens and retina and contributes to established multi-nutrient eye formulas. Used alone, it cannot replace macular carotenoids, vitamin E, zinc, or omega-3 support.

The buffered calcium ascorbate form supplies a very large disclosed amount. The amount approaches the usual adult daily upper limit and may cause diarrhea or stomach cramps in sensitive users.

Study evidence
Vitamin C Disputed 24 studies
Anti-Inflammatory Support
Anti-Inflammatory Support
Impact
High effect
C- Goal FitA- Strength of SupportD CoverageA+ Formula Quality
Vitamin C · 1760 mg

High-dose calcium ascorbate provides focused antioxidant support in a buffered form. It remains an indirect inflammation tool with narrow pathway coverage.

It may suit users who tolerate buffered vitamin C better than ascorbic acid. The high amount can still cause digestive upset in sensitive users.

Study evidence
Vitamin C Supportive 50 studies
Skin Health
Skin Health
Impact
High effect
B- Goal FitB- Strength of SupportC- CoverageA- Formula Quality
Vitamin C · 1760 mg

Calcium ascorbate supplies buffered vitamin C for normal collagen synthesis and antioxidant defense. The very large serving may reduce absorption efficiency and cause digestive upset despite the gentler form.

The minimal formula offers depth for one supporting nutrient but no collagen, ceramides, or direct hydration active. Clear vitamin C and calcium amounts support transparency.

Study evidence
Vitamin C Supportive 53 studies

Ingredients

IngredientAmount per serving
Vitamin C (Calcium Ascorbate)
 1760 mg
Calcium (Calcium Ascorbate)
 180 mg
Gluten Free Adults 18–50 Vegan Dairy Free Vegetarian
Report overview
Vitamin C (Calcium Ascorbate) · 1760 mg OverallScore86
B+ Active Ingredient Quality & BioavailabilityB+ Dose, Safety & Label TransparencyA+ Value

Calcium ascorbate provides 1,760 mg of buffered vitamin C with lower acidity than plain ascorbic acid. The label clearly separates vitamin C from the 180 mg of calcium, and the ingredient list is simple. Cost efficiency is exceptional, though the serving is above the preferred absorption-focused range.

View ingredientView products
Loading alternative details
89 Performance

Pure Buffered Calcium Ascorbate

NOW
A more performance-focused option combines 890 mg of vitamin C as Calcium Ascorbate with 100 mg of Calcium. Compared with the original's 1,760 mg of vitamin C as Calcium Ascorbate, the smaller amount favors moderate daily use but provides less vitamin C per serving.
88 Performance

Buffered Gold C

California Gold Nutrition
A more performance-focused option combines 1,000 mg of vitamin C as Sodium Ascorbate with a focused single-nutrient formula. Compared with the original's 1,760 mg of vitamin C as Calcium Ascorbate, the smaller amount favors moderate daily use but provides less vitamin C per serving.
85 Performance

Ester-C Plus 1000 mg Vitamin C

Solgar
A more performance-focused option combines 1,000 mg of vitamin C as Ester-C with 108 mg of Calcium and 200 mg of Citrus Bioflavonoids Complex. Compared with the original's 1,760 mg of vitamin C as Calcium Ascorbate, the smaller amount favors moderate daily use but provides less vitamin C per serving.
87 Budget

Pure Buffered Magnesium Ascorbate

NOW
The lower serving cost still provides 820 mg of vitamin C as Magnesium Ascorbate with 60 mg of Magnesium. Compared with the original's 1,760 mg of vitamin C as Calcium Ascorbate, the smaller amount favors moderate daily use but provides less vitamin C per serving.
84 Budget

Ester-C 500 mg With Citrus Bioflavoinds

American Health
The lower serving cost still provides 1,000 mg of vitamin C as Ester-C Calcium Ascorbate with 110 mg of Calcium and 400 mg of Citrus Bioflavonoids Complex. Compared with the original's 1,760 mg of vitamin C as Calcium Ascorbate, the smaller amount favors moderate daily use but provides less vitamin C per serving.
88 Budget

Sodium Ascorbate

NutriBiotic Immunity
The lower serving cost still provides 1,100 mg of vitamin C as Sodium Ascorbate with a focused single-nutrient formula. Compared with the original's 1,760 mg of vitamin C as Calcium Ascorbate, the smaller amount favors moderate daily use but provides less vitamin C per serving.
85 Value

C-500 With Rose Hips

NOW
The favorable serving cost pairs 500 mg of vitamin C as Ascorbic Acid with 40 mg of Rose Hips powder. Compared with the original's 1,760 mg of vitamin C as Calcium Ascorbate, the smaller amount favors moderate daily use but provides less vitamin C per serving.
87 Value

100% Pure Vitamin C Powder

Swanson Premium Brand
The favorable serving cost pairs 1,000 mg of vitamin C as Ascorbic Acid with a focused single-nutrient formula. Compared with the original's 1,760 mg of vitamin C as Calcium Ascorbate, the smaller amount favors moderate daily use but provides less vitamin C per serving.
87 Value

C 500 mg

Mason Natural
The favorable serving cost pairs 500 mg of vitamin C as Ascorbic Acid with a focused single-nutrient formula. Compared with the original's 1,760 mg of vitamin C as Calcium Ascorbate, the smaller amount favors moderate daily use but provides less vitamin C per serving.
Report alternatives

Sources

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

  1. 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
  2. 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
  3. 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
  4. 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
  5. 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
  6. 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
  7. 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
  8. 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
  9. 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
  10. 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
  11. 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
  12. 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
  13. 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
  14. 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
  15. 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
  16. 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
  17. 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
  18. 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
  19. 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
  20. 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
  21. 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
  22. 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
  23. Nutritional modulation of cataract.
    Weikel KA; Garber C; Baburins A; Taylor A · Nutrition reviews · 2014
    Narrative reviewVision Support forVitamin C
  24. 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
  25. 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