Effects of proteoglycan supplementation on knee joint health and walking function in healthy adults: A randomized double-blind placebo-controlled trial
DOI:
https://doi.org/10.31989/ffhd.v16i4.1978Abstract
Background: Age-related declines in joint function and walking ability represent an important issue, as they are associated with limitations in daily activities and reduced quality of life. Therefore, many people are interested in dietary components that support joint health.
Objective: Proteoglycan (PG) is a glycosylated protein and a key component of the extracellular matrix in articular cartilage. Previous studies have shown that PG supplementation leads to significant improvements in knee pain. This study aimed to investigate the effects of PG intake on knee joint and walking function in healthy individuals.
Methods: A randomized, double-blind, placebo-controlled trial was conducted in healthy participants with age-related joint discomfort, reduced walking ability, and decreased muscle strength. 58 participants aged 40 to 74 years (mean age: 55.0 years) were randomly assigned to receive either PG-containing capsules or placebo capsules for 12 weeks. The PG capsule contains 10 mg PG with an approximate molecular weight of 450,000. Changes in subjective symptom questionnaires and walking performance, assessed using a 6-meter walk test, were analyzed.
Results: After 12 weeks of PG intake, significant differences between groups were observed in the changes from baseline in visual analog scale (VAS) scores at rest and while kneeling, as well as in walking speed.
Conclusions: The present findings suggest that PG supplementation may help alleviate age-related functional declines in walking and knee pain.
Novelty of the Study: While previous studies have demonstrated that PG supplementation improves knee pain, evidence regarding its influence on functional mobility in healthy adults remains limited. This study is among the first randomized controlled trials to examine the impact of PG supplementation on walking pace in individuals without diagnosed joint disease, supporting its application as a functional food ingredient for proactive joint health management.
Trial Registration: UMIN-CTR: UMIN000052712
Keywords: Proteoglycan; bioactive compounds; functional food ingredient; knee joint health; walking performance; age-related joint discomfort; articular cartilage; salmon
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