Allergy Research Group Esterol Ester-C® - 100 vegetarian capsules bottle front label

Supplement Facts panel for Esterol Ester-C showing vitamin C nutrient information, serving size, and daily value details

Esterol Ester-C® - suggested use: 2 capsules daily with meals

Esterol Ester-C® - Ester-C® Buffered Vitamin C ingredient benefits overview

SKU 70080

Esterol Ester-C®

Calcium Ascorbate with Bioflavonoids

This product has been discontinued and is no longer available for purchase.

Esterol Ester-C® provides highly bioavailable vitamin C as Ester-C® calcium ascorbate, buffered for improved tolerance and supported by bioflavonoids quercetin, rutin, and grape seed extract.* Research shows Ester-C® enhances vitamin C uptake by immune cells, promotes immune resilience, supports antioxidant defenses, and aids in collagen, adrenal, and connective tissue health.* Two capsules of Esterol Ester-C® contain 1.35 grams of vitamin C as calcium ascorbate.

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Ingredients

Serving Size: 2 capsules
Servings Per Container: 50 or 100

Amount per serving:

Vitamin C (as Calcium Ascorbate): 1.35 g
Calcium (as Calcium Ascorbate): 150 mg
Rutin: 100 mg
Quercetin Dihydrate: 50 mg
Grape Seed Extract (92% Proanthocyanidins): 5 mg

Other Ingredients

Hydroxypropyl methylcellulose, magnesium stearate, silicon dioxide.

Suggested Use

As a dietary supplement, take 2 capsules daily with meals, or as directed by a healthcare practitioner.

If you are pregnant or lactating, have any health condition or are taking any medication, consult your healthcare practitioner before use.

Store in a cool, dry place, tightly capped, away from light. Keep out of the reach of children. Use only if safety seal is intact. Variations in product color may occur.

Esterol Ester-C®

$59.29

What It Does

Esterol Ester-C® provides highly bioavailable vitamin C as Ester-C® calcium ascorbate, a non-acidic, buffered form designed for optimal gastrointestinal tolerance and cellular uptake.* This formula supports immune resilience, antioxidant defenses, collagen formation, adrenal function, and connective tissue health.*

How It Works

• Ester-C® (calcium ascorbate, 1.35 g per 2 capsules): A unique, pH-neutral form of vitamin C with added metabolites that enhances uptake into white blood cells and prolongs retention for sustained biological activity.*[1-3]
• Bioflavonoids (quercetin, rutin, grape seed extract): Provide additional antioxidant activity, helping stabilize vitamin C while contributing vascular, immune, and connective tissue benefits.*[10,11]
• Buffered Formulation: Calcium ascorbate is gentler on the stomach and may reduce the risk of oxalate formation compared to ascorbic acid.*[8,9]
• Enhanced Immune Cell Activity: Clinical studies show Ester-C® supports improved neutrophil and NK cell function, histamine metabolism, and white blood cell activity compared to regular vitamin C.*[2,3,5]
• Adrenal and Connective Tissue Support: Vitamin C is concentrated in adrenal glands and plays a vital role in collagen synthesis and stress hormone production.*[6,7]

Who It's For

Ideal for individuals seeking a well-tolerated, highly bioavailable form of vitamin C to support immune, antioxidant, and tissue health, especially those sensitive to acidic forms or with increased vitamin C needs.*

Special Features

This formula combines 1.35 grams of buffered vitamin C with complementary bioflavonoids to mirror nature’s delivery system, enhancing cellular uptake and tolerability. It is free from common allergens and formulated for clinical efficacy.*

References

1. Gruenwald J, et al. Adv Ther. 2006;23(1):171–178.
2. Calder PC, et al. Nutrients. 2025;17(2):279. doi:10.3390/nu17020279
3. Mitmesser SH, et al. Springerplus. 2016;5(1):1161. doi:10.1186/s40064-016-2605-7
4. Bush MJ, Verlangieri AJ. Res Commun Chem Pathol Pharmacol. 1987;57(1):137–140.
5. Verlangieri AJ, et al. Life Sci. 1991;48(23):2275–2281.
6. Dickerson B, et al. Nutrients. 2024;16(19):3358. doi:10.3390/nu16193358
7. Moyad MA, et al. Adv Ther. 2008;25(10):995–1009.
8. Van Straten M, Josling P. Adv Ther. 2002;19(3):151–159.
9. Moyad MA, et al. Urol Nurs. 2009;29(2):95–102.
10. Ganeshpurkar A, Saluja AK. Saudi Pharm J. 2017;25(2):149–164.
11. Deepika, Maurya PK. Molecules. 2022;27(8):2498. doi:10.3390/molecules27082498

Additional Information

Buffered Vitamin C with Enhanced Immune Uptake and Antioxidant Support*

Esterol Ester-C®

Calcium Ascorbate with Bioflavonoids

One-Time Purchase

Subscribe & Save 10%

Choose Your Size

What It Does

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