Oral Collagen Supplementation: A Systematic Review of Dermatological Applications
January 2019 | Volume 18 | Issue 1 | Original Article | 9 | Copyright © January 2019
Franchesca D. Choi BS RPh,a,b Calvin T. Sung BS,a,c Margit L.W. Juhasz MD,a Natasha Atanaskova Mesinkovska MD PhDa
aUniversity of California, Irvine, Department of Dermatology, Irvine, CA bKaohsiung Medical University, School of Post-Baccalaureate Medicine, Kaohsiung, Taiwan cUniversity of California, Riverside, School of Medicine, Riverside, CA
IMPORTANCE: The use of nutraceuticals such as collagen for skincare has been rising, but regulations are lacking on quality, absorption, and efficacy. To address this knowledge gap, clinical studies regarding the potential effects of collagen-based dietary supplements on skin are being completed. OBJECTIVE: To review the literature and assess available randomized-controlled trials using collagen supplementation for treatment efficacy regarding skin quality, anti-aging benefits, and potential application in medical dermatology. EVIDENCE REVIEW: A literature search was conducted with PubMed using search criteria (collagen) AND (supplement OR food OR nutrition). No lower limit on the year of publication was set. Inclusion criteria were: randomized, placebo-controlled trials using collagen supplementation in human subjects related to dermatology and written in English. FINDINGS: Eleven studies with a total of 805 patients were included for review. Eight studies used collagen hydrolysate, 2.5g/d to 10g/d, for 8 to 24 weeks, for the treatment of pressure ulcers, xerosis, skin aging, and cellulite. Two studies used collagen tripeptide, 3g/d for 4 to 12 weeks, with notable improvement in skin elasticity and hydration. Lastly, one study using collagen dipeptide suggested anti-aging efficacy is proportionate to collagen dipeptide content. CONCLUSIONS AND RELEVANCE: Preliminary results are promising for the short and long-term use of oral collagen supplements for wound healing and skin aging. Oral collagen supplements also increase skin elasticity, hydration, and dermal collagen density. Collagen supplementation is generally safe with no reported adverse events. Further studies are needed to elucidate medical use in skin barrier diseases such as atopic dermatitis and to determine optimal dosing regimens. J Drugs Dermatol. 2019;18(1):9-16.
Nutrition is thought to play an important role in skin homeostasis. The use of nutraceuticals or “functional foods” in skincare along with technological innovations within the food industry has been rising.1 In 2016, the collagen market was valued at an estimated 3.71 billion USD and is projected to reach 6.63 billion USD by 2025.2,3 Collagen supplements, originating from various sources (eg, porcine, bovine, marine) and available in numerous formulations (eg, protein, gelatin, hydrolysate, peptides), are marketed as improving skin integrity and modulating skin aging.4 However, even with this increase in patient interest and market share, the use of collagen supplementation in dermatology remains controversial due to the lack of regulation on quality and quantity of ingredients in over-the-counter collagen supplements, as well as minimal peer-reviewed literature on the subject. Fortunately, there are increasing numbers of clinical studies regarding potential effects of collagen-based dietary supplements on skin. Collagen is the most abundant component of the extracellular matrix constituting 75% of skin’s dry weight.5 Qualitative and quantitative decline in collagen is associated with cutaneous aging.6 Collagen protein is a right-handed triple helix of parallel polypeptides where every third amino acid residue is glycine (Gly) resulting in X-Y-Gly triplets, where X andY are frequently proline (Pro) and 4-hydroxyproline (Hyp; an amino acid sub- unit unique to collagen), respectively,7 making Pro-Hyp-Gly the most common amino acid triplet unit found in collagen.8,9 Native, animal collagen can be extracted from connective tissue in various forms.10 When denatured by heat, collagen forms gelatin, which has been used for centuries as a food source and traditional medicine in Europe and China.9 Further enzymatic hydrolysis of gelatin produces collagen hydrolysates (CH) composed of peptides of varying lengths. CH has a lower molecular weight than gelatin, higher water-solubility, and no gelation properties at ambient temperatures, allowing CH to be conveniently formulated into liquid drinks and jelly sticks for oral consumption. In the past decade, CHs have gained popularity as a nutraceutical supplement.11–13