UC-II Undenatured Type II Collagen for Knee Joint Flexibility: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Clinical Study

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#adult #collagen-type-ii #humans #knee-joint #middle-aged

UC-II Undenatured Type II Collagen for Knee Joint Flexibility: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Clinical Study

Schön et al., 2022 | J Integr Complement Med | Rct

Citation

Schön Christiane, Knaub Katharina, ... Juturu Vijaya. UC-II Undenatured Type II Collagen for Knee Joint Flexibility: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Clinical Study. J Integr Complement Med. 2022-Jun;28(6):540-548. doi:10.1089/jicm.2021.0365

Abstract

Objective: Joint-related stress models have been used in the past to induce a standardized load on physical structures, allowing researchers to observe changes in perceived stress on joints as accurately as possible in healthy individuals. Previous studies support the efficacy of UC-II® undenatured type II collagen ("undenatured collagen") supplementation in maintaining joint health. The purpose of this study was to assess the effect of undenatured collagen on knee flexibility in healthy subjects who experience activity-related joint discomfort (ArJD). Methods: This randomized, double-blind, placebo (PLA)-controlled study was conducted in healthy subjects with ArJD who had no history of osteoarthritis, or joint diseases. Ninety-six (n = 96, 20-55 years old) subjects who reported joint discomfort while performing a standardized single-leg-step-down test were randomized to receive either PLA (n = 48) or 40 mg of undenatured collagen (n = 48) supplementation daily for 24 weeks. Range of motion (ROM) flexion and extension were measured using a digital goniometer. Results: At the end of the study, a statistically significant increase in knee ROM flexion was observed in the undenatured collagen group versus the PLA group (3.23° vs. 0.21°; p = 0.025). In addition, an increase in knee ROM extension by 2.21° was observed over time in the undenatured collagen group (p = 0.0061), while the PLA group showed a nonsignificant increase by 1.27° (p > 0.05). Subgroup analysis by age showed a significant increase in knee ROM flexion in subjects >35 years old in the undenatured collagen supplemented group compared with PLA (6.79° vs. 0.30°; p = 0.0092). Conclusion: Overall, these results suggest that daily supplementation of 40 mg of undenatured collagen improved knee joint ROM flexibility and extensibility in healthy subjects with ArJD.

Key Findings

At the end of the study, a statistically significant increase in knee ROM flexion was observed in the undenatured collagen group versus the PLA group (3.23° vs. 0.21°; p = 0.025). In addition, an increase in knee ROM extension by 2.21° was observed over time in the undenatured collagen group (p = 0.0061), while the PLA group showed a nonsignificant increase by 1.27° (p > 0.05). Subgroup analysis by age showed a significant increase in knee ROM flexion in subjects >35 years old in the undenatured

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population healthy individuals
Sample Size 96
Age Range 20-55 years
Condition stress

MeSH Terms

  • Adult
  • Collagen Type II
  • Humans
  • Knee Joint
  • Middle Aged
  • Range of Motion, Articular
  • Young Adult

Evidence Classification

  • Level: Rct
  • Publication Types: Journal Article, Multicenter Study, Randomized Controlled Trial
  • Vertical: collagen-joint

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09