Liposomal Delivery Enhances the Effects of a Collagen Tripeptide-Containing Formulation on Dermal Structure and Optical Skin Parameters: A Randomized, Double-Blind, Placebo-Controlled Trial

Abstract

Objective This study aimed to determine whether liposomal delivery enhances the effects of a collagen tripeptide-containing formulation on dermal structural and biomechanical parameters, as well as appearance-related skin properties, compared with a nonliposomal formulation and placebo. Methods In a randomized, double-blind, placebo-controlled trial, 75 healthy adults aged 25-65 years were assigned to receive placebo, a nonliposomal formulation containing collagen tripeptides, or a liposomal formulation containing collagen tripeptides (50 mL/day) for 8 weeks. Objective assessments of dermal collagen density, skin hydration, elasticity, wrinkle area, skin luminance, and tone evenness were performed at baseline and Weeks 2, 4, and 8 using standardized instrumental measurements. Results Both collagen tripeptide-containing formulation groups showed significant improvements in dermal collagen density, hydration, and elasticity compared with placebo (p < 0.05). The liposomal formulation demonstrated an earlier onset and a greater magnitude of improvement across multiple parameters, with a statistically significant advantage in skin elasticity at Week 8 compared with the nonliposomal formulation (p < 0.05). Notably, only the liposomal collagen tripeptide-containing formulation group exhibited a significant reduction in wrinkle area at Week 8 relative to placebo (p < 0.05). Both collagen tripeptide formulation groups also showed significant increases in skin luminance and tone evenness. Conclusion Liposomal delivery significantly enhances the functional effects of a collagen tripeptide-containing formulation on dermal structure and biomechanical performance, particularly dermal collagen density and skin elasticity, as well as optical skin properties including luminance and tone evenness. These findings support the application of liposomal formulations containing collagen tripeptides as an effective oral nutricosmetic strategy for improving visible signs of skin aging.