Proteoglycans are major structural components of cartilage, where they contribute to the tissue’s resilience and load-bearing properties by attracting and retaining water. Their degradation is a hallmark of cartilage damage in conditions such as osteoarthritis. Scientific interest in supplementing or supporting proteoglycan levels to treat cartilage damage has grown in recent decades. Several studies, mainly preclinical and small-scale clinical trials, have evaluated the effects of proteoglycan supplementation—often in the form of extracts from salmon nasal cartilage or similar sources—on joint health and cartilage repair.

Some evidence suggests that oral or injectable proteoglycan supplements may help reduce inflammation, slow cartilage degradation, and promote cartilage repair, likely by modulating chondrocyte activity and suppressing inflammatory mediators. However, the clinical evidence remains preliminary, with a limited number of high-quality randomized controlled trials. While results have been encouraging in animal models and in vitro studies, human data are not yet robust, and the long-term efficacy and optimal dosing remain unclear.

Overall, the use of proteoglycan supplements to support or treat cartilage damage is grounded in a solid mechanistic rationale and supported by some early scientific evidence, but more rigorous and large-scale clinical research is needed to establish clear recommendations for their use.