Written by Angeline A. De Leon, Staff Writer. Of the eighty-five Chinese female participants, those who consumed H-CP (collagen hydrolysate with a higher ratio of bioactive dipeptides) had significantly increased skin moisture at cheek and corners of eyes compared to those who consumed L-CP (collagen hydrolysate with a lower ratio of bioactive dipeptides) and placebo.

skin healthCollagen, is the main component of connective tissue, is made up of different amino acids and represents the most abundant protein in the body. Through its promotion of strength and elasticity, this essential protein helps give structure to hair, skin, nails, ligaments, and bones. In cosmetology, supplementation with a form of collagen, essentially a digestible gelatin protein known as collagen hydrolysates, is routinely employed to improve facial spots, reduce wrinkle volume, and maintain skin elasticity 1. Collagen hydrolysates are popular due to their low molecular weight, solubility in water, and quick absorption into the body, which allows them to be marketable as drink- and jelly-stick-form products 2. In vitro studies, looking at the bioactive peptides derived from collagen hydrolysates, have identified two major types of collagen dipeptides that may influence how collagen hydrolysates work to improve skin conditions 1. Associated with stimulation of skin cell activity and enhanced production of hyaluronic acid 3,4, prolyl-hydroxyproline (Pro-Hyp) and hydroxyprolyl-glycine (Hyp-Gly) appear to reach skin and bone tissues quickly following ingestion and remain stable in the blood stream for several hours 5,6. Given their involvement in physiological processes at the dermal level, researchers have become interested in understanding the role of collagen peptides in improving skin health. In a study published in the Journal of the Science of Food and Agriculture (2016), scientists compared the efficacy of two collagen hydrolysates with varying concentrations of Pro-Hyp and Hyp-Gly.

In a randomized, double-blind, placebo-controlled study, a total of 85 Chinese female volunteers were recruited as participants. Subjects were randomized to one of three groups, in which they orally ingested 5 g samples of either L-CP (collagen hydrolysate with low ratio of dipeptide-to-product content, about 0.1 g kg-1 of product), H-CP (collagen hydrolysate with high ratio of dipeptide-to-product content, more than 2 g kg-1 of product), or placebo, which were dissolved in hot milk, coffee, or another beverage daily for eight weeks. At baseline and after 4 and 8 weeks of supplementation, skin conditions were evaluated based on skin moisture, skin elasticity, and skin wrinkles and roughness.

Results of the study indicated that by week 8, the H-CP group had significantly increased skin moisture at the cheek and corner of the eyes, compared to both the L-CP group and placebo (p < 0.05 for both). H-CP also exhibited significantly greater elasticity of these facial areas, relative to placebo (p < 0.05), from baseline to week 8, with a change rate of improvement that was significantly greater than that of the L-CP group (p < 0.05). Moreover, skin surface analysis showed that H-CP subjects experienced significant reductions, relative to L-CP and placebo, in number of wrinkles by week 8 and depth of wrinkles and skin roughness by weeks 4 and 8 (p < 0.05).

General findings illustrate the ability of fortified collagen hydrolysate, H-CP, to improve various aspects of skin health, including moisture, roughness, elasticity, and appearance of wrinkles. This study also highlights the qualitative difference in outcome associated with collagen hydrolysate products with higher contents of specific peptides (such as Pro-Hyp and Hyp-Gly) vs. other conventional forms of collagen. Future research is still needed to understand the fundamental mechanisms underlying the activity of bioactive peptides.

Source: Inoue N, Sugihara F, and Wang X. Ingestion of bioactive collagen hydrolysates enhance facial skin moisture and elasticity and reduce facial aging signs in a randomised double-blind placebo-controlled clinical study. Journal of the Science of Food and Agriculture. 2016; 96: 4077-4081. DOI: 10.1002/jsfa.7606.

© 2016 Society of Chemical Industry

Posted January 8, 2018.

Angeline A. De Leon, MA, graduated from the University of Illinois at Urbana-Champaign in 2010, completing a bachelor’s degree in psychology, with a concentration in neuroscience. She received her master’s degree from The Ohio State University in 2013, where she studied clinical neuroscience within an integrative health program. Her specialized area of research involves the complementary use of neuroimaging and neuropsychology-based methodologies to examine how lifestyle factors, such as physical activity and meditation, can influence brain plasticity and enhance overall connectivity.


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