NBTY says this is the first clinical trial to compare vitamin C retention in leukocytes between ascorbic acid and Ester-C in both men and women.
New clinical study results published in SpringerPlus suggest Ester-C vitamin C stays in white blood cells (leukocytes) longer than conventional vitamin C from ascorbic acid. According to Ester-C manufacturer NBTY (Ronkonkoma, NY), this is “the first clinical trial comparing vitamin C retention in leukocytes between Ester-C and ascorbic acid in both male and female nonsmokers.”
The double-blind, placebo-controlled, crossover trial contained 36 subjects aged 18–60 who were randomized to consume either 1000 mg of ascorbic acid vitamin C, 1000 mg of Ester-C vitamin C, or a placebo, with each administration preceded by a 7-day washout period. Researchers then measured plasma and leukocyte vitamin C concentrations at baseline and 2, 4, 8, and 24 hours post-dose.
With the Ester-C administration, the concentration change of leukocyte vitamin C from baseline was significantly increased at 24-hours post-dose. The placebo and ascorbic acid administrations, on the other hand, showed no significant within-group changes to mean leukocyte vitamin C concentration. The Ester-C administration also resulted in significantly higher percent changes to leukocyte vitamin C concentration at 8- and 24-hours post-dose compared to ascorbic acid. No significant differences were found between Ester-C and ascorbic acid when it came to changing vitamin C plasma concentration.
Researchers concluded that “[Ester-C] significantly increased leukocycte vitamin C levels compared to [ascorbic acid] and [placebo],” possibly due to metabolites in Ester-C which have previously been shown to enhance vitamin C retention and facilitate absorption.
“Ester-C is the only product of its kind on the market, and customers can easily find it by the ’24-hour immune support’ call out on the label,” said John Frame, vice president of marketing for Ester-C. “This product has been clinically studied to stay in the white blood cells longer than regular vitamin C-a distinct advantage to anyone looking to nutritionally support their immune system all day long.”
Nutritional Outlook Magazine
Mitmesser SH et al., “Determination of plasma and leukocyte vitamin C concentrations in a randomized, double-blind, placebo-controlled trial with Ester-C,” SpringerPlus. Published online July 25, 2016.