Esterol contains vitamin C in the form of Ester-C® calcium ascorbate, and the bioflavonoids quercetin, rutin, and proanthocyanidins from grape seed extract. Several studies suggest that the unique structure of Ester-C® may make it more readily absorbed and less rapidly excreted than other forms of vitamin C.* Rapid cellular uptake and delayed renal excretion of ascorbic acid are conducive to providing optimum cellular concentration for biochemical activity.* Ester-C® has a pH of 7.0, potentially reducing acidity and improving bowel tolerance.* Bioflavonoids work synergistically with vitamin C.*
|Serving Size: 2 Capsules||Amount Per Serving|
|Vitamin C (as calcium ascorbate)
|Calcium (as calcium ascorbate)
|Grape Seed Extract (92% Proanthocyanidins)
Other Ingredients: Hydroxypropyl methylcellulose, magnesium stearate, silicon dioxide
As a dietary supplement, 1 or 2 capsules one or two times daily between meals, or as directed by a healthcare practitioner.
Researchers at the University of Mississippi School of Pharmacy compared the effects of ingesting Ester-C® and L-ascorbic acid, using special rats that lack the L-gulonolactone oxidase necessary for the synthesis of vitamin C (a trait shared with human beings). Ester-C® showed slower excretion and higher plasma values of ascorbic acid, providing increased cellular concentration for biochemical activity.* A human study showed similar results for Ester-C®, including significantly higher serum levels than L-ascorbic acid at 4, 8 and 24 hours after ingestion, as well as after 7-10 days of continuous ingestion; significantly higher white blood cell levels at 8 and 24 hours after ingestion and after 7-10 days of continuous ingestion; substantially less oxalate excretion in the first 24 hours after ingestion, as well as after 7-10 days of continuous ingestion; and substantially less urinary ascorbate loss in both the first 24 hours of ingestion and after 7-10 days of continuous ingestion.* A 2009 randomized, double-blind, crossover study at the University of Michigan Medical Center in Ann Arbor found that Ester-C® significantly reduced urine oxalate levels compared to ascorbic acid.*