Tier 2 — strong

Oral Intake of Low-Molecular-Weight Collagen Peptide Improves Hydration, Elasticity, and Wrinkling in Human Skin: A Randomized, Double-Blind, Placebo-Controlled Study

Do-Un Kim, Hee-Chul Chung, Jia Choi, Yasuo Sakai, Boo-Yong Lee

Nutrients 2018 10(7):826

Bibliography

DOI: 10.3390/nu10070826
PubMed: PMID 29949889
PubMed Central: PMC6073484
Funding: This research received no external funding.
Competing interests: The authors and the company, Newtree Co., Ltd., declare no conflict of interest to any extent. Editorial note: Despite the formal declaration of no conflict, three of five co-authors hold direct commercial affiliations to the test material's supply chain. Kim and Chung are employees of Newtree (Seongnam, Korea), which supplied the LMWCP test material. Sakai is employed by Jellice (Tagajo, Japan), a collagen ingredient manufacturer. This constitutes a substantial undisclosed commercial interest.

Study snapshot

Design	Randomised, double-blind, placebo-controlled parallel-group trial
Model	Korean women aged 40–60 with photoaged skin (crow's-feet global photodamage score 2–6)
Sample	n=64 randomised (33 test, 31 placebo); n=53 completed (26 test, 27 placebo)
Intervention	1000 mg/day low-molecular-weight collagen peptide (LMWCP; fish-derived sutchi catfish Pangasius hypophthalmus skin, >15% tripeptide content including 3% Gly-Pro-Hyp) in a 50 mL bottle vs vehicle placebo. Both arms contained 100 mg vitamin C, fruit concentrate, flavour, excipients, and sweetener.
Duration	12 weeks intake plus 2-week washout for safety
Endpoints	Skin hydration (Corneometer CM 825); skin wrinkling by visual dermatologist grade using global photodamage scoring; instrumental skin wrinkling parameters R1–R5 (Skin Visiometer SV600); skin elasticity parameters R2, R5, R7 (Cutometer MPA 580); adverse events, blood chemistry, urinalysis, vital signs

What the study showed, in plain terms

Researchers gave 64 Korean women aged 40 to 60 either a daily drink containing 1000 mg of a specially prepared fish-derived collagen peptide or an identical-tasting placebo drink. Every woman had visible sun-related skin damage around the eyes at the start. After 6 and 12 weeks, dermatologists measured how hydrated, wrinkled, and elastic their skin was using standardised skin instruments.

The collagen group saw meaningfully greater improvements in skin hydration by week 6 and week 12 than the placebo group did. Their crow's-feet wrinkle scores improved significantly by week 12, alongside three of five instrumental wrinkle measurements. Two of three elasticity measurements were also better than in the placebo group by week 12. No participants reported any side effects from the collagen drink over the trial period.

The finding matters because it is one of the earliest well-conducted human trials showing that a low-molecular-weight collagen peptide with a high tripeptide content can produce measurable skin improvements at a relatively modest daily dose. It does not, however, tell us how the effect compares to other collagen preparations, or whether the improvements persist after stopping the supplement.

Key findings

Skin hydration in the LMWCP group rose significantly from baseline at 6 weeks (p<0.001) and 12 weeks (p<0.001); placebo saw no change at 6 weeks but a smaller significant rise at 12 weeks.
Between-group hydration gain was 7.23-fold greater in LMWCP than placebo at 6 weeks and 2.9-fold greater at 12 weeks.
Visual crow's-feet wrinkle grade improved significantly from baseline at 12 weeks in the LMWCP group (p<0.001) but not in placebo. Between-group difference significant at 12 weeks (p=0.013).
Instrumental wrinkling parameters R1 (skin roughness, p=0.043), R3 (average roughness, p=0.025), and R4 (smoothness depth, p=0.004) were significantly better in LMWCP than placebo at 12 weeks.
Skin elasticity R5 (net elasticity) rose significantly from baseline in LMWCP at 12 weeks (p=0.002); between-group R2 (overall elasticity, p=0.025) and R5 (p=0.027) were both significantly higher than placebo at 12 weeks.
No adverse reactions reported. All blood chemistry, urinalysis, and vital-sign parameters remained within normal ranges.

What this study can and cannot tell us

Sample was single-sex (women only), single-ethnicity (Korean), and single-age-band (40–60). Results cannot be generalised to men, to other ethnicities, or to older or younger adults without confirmatory trials.
Only one dose was tested (1000 mg/day). The trial provides no dose-response information and cannot address whether lower or higher doses would produce different effects.
12-week duration is short. Whether the improvements are durable, plateau, or continue with longer supplementation is unknown. No follow-up after cessation.
The placebo group also showed a significant hydration increase at 12 weeks. The authors attribute this to the vehicle formulation (vitamin C, fruit concentrate) and to the study's ban on other cosmetic products. This means the isolated effect of LMWCP alone is smaller than the raw within-group change suggests.
Elasticity findings were mixed: R5 improved from baseline in LMWCP but R2 within-group was borderline (p=0.088). Only the between-group comparison for R2 reached significance, and R7 showed no effect at all.
Substantial undisclosed commercial interests — three of five authors are employed by the test material's manufacturer or a related collagen supplier. The formal declaration of no conflict is not credible on the record shown.
The proposed mechanism (Pro-Hyp stimulation of hyaluronic acid via HAS2) is hypothesised from prior in vitro literature; this trial did not measure any mechanistic biomarker directly.

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