Undenatured type II collagen for knee osteoarthritis in people and animals
What it found
In people with knee osteoarthritis, 40 mg of undenatured type II collagen daily reduced pain and improved joint movement over several months.
Animal studies showed similar benefits at matching doses.
What they found
Studies in people
Joint pain in people
Across multiple trials in people with knee osteoarthritis, taking 40 mg of this collagen daily lowered pain scores compared to a dummy pill or no treatment. Benefits were seen over follow-up periods ranging from 6 weeks to 180 days.
Movement and flexibility in people
People taking the collagen could bend and straighten their knees further than those taking a dummy pill. They also walked longer distances in timed tests and climbed stairs with less difficulty.
Comparison with other supplements
Several trials in people compared 40 mg of this collagen daily against a mix of glucosamine and chondroitin. Both approaches eased pain and stiffness, but the collagen group sometimes reported better overall quality of life.
Side effects in trials
Human trials lasting up to 180 days reported no serious unwanted effects linked to taking 40 mg of the collagen daily. Safety results were similar between the collagen groups and the comparison groups.
Animal and lab studies
Results in rats and mice
In rats and mice with induced joint damage, doses matching 40 to 120 mg per day in humans improved walking patterns and lowered markers of swelling. Higher doses generally worked better than lower ones in these animals.
Other findings
How it works in the gut
After being swallowed, the collagen reaches immune tissue near the small intestine. This trains certain immune cells to travel to the joints and release signals that lower swelling and may support cartilage repair.
What the authors conclude
- They conclude that taking 40 mg of undenatured type II collagen daily can reduce pain and improve joint movement in the short and medium term.
- They advise that larger trials lasting longer are needed to confirm whether these benefits hold up over many years.
- They call for more research comparing this collagen directly to standard medical treatments like steroid injections.
How it was done
Standard treatments for knee osteoarthritis often have side effects and only ease pain without fixing the underlying joint damage. The authors wanted to see if a supplement made from chicken cartilage could help by targeting the cause of the problem.
The authors searched medical databases for all lab, animal and human studies on undenatured type II collagen for knee osteoarthritis published up to August 2024. They found 12 studies that met their criteria: three in animals, eight in people, and one combining both. They also checked trial registries for any ongoing research.
What it can’t tell you
- Most human trials followed people for six months or less, so scientists do not yet know if the benefits last longer.
- A review gathers existing work but cannot prove cause and effect on its own.
- Results seen in rats and mice might not match what happens in human bodies.
Who paid
- Conflicts
- The authors report no conflict of interest.
- Authors work at
- University of Salerno, Italy; Sapienza University of Rome, Italy; Queen Mary University of London, UK
The paper
- Title
- Undenatured type II collagen for knee osteoarthritis
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Cite
- Gupta A, Maffulli N (2025). Undenatured type II collagen for knee osteoarthritis. Annals of medicine. doi:10.1080/07853890.2025.2493306Free full textPubMed 40253594DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error