Collagen is a protein found in many parts of the human body, including the cartilage between bones. Collagen makes up for articular cartilage, the tissue that covers the ends of bones at the joints and allows them to move smoothly against one another.
Since collagen is made up of amino acids, the building blocks of protein, it has been known that the body can use the amino acids in collagen supplements to protect and rebuild joint cartilage as well. Diseases like osteoarthritis and rheumatoid arthritis are degenerative in nature which can damage the joint cartilage. The research on the effect of collagen supplements on joints is minimal, yet promising.

Collagen type I and II are most often used to treat pain in osteoarthritis and rheumatoid arthritis. Collagen is said to work by causing the body to produce substances that fight inflammation, but this has not been proven.

Research shows that collagen may have a positive effect on different types of arthritis pain. A 2016 study noted the effects of collagen supplements on individuals with osteoarthritis results that shows that collagen reduced pain, stiffness and mobility. A 2009 study that involved participants with RA also shows that taking collagen improved pain, morning stiffness, tenderness and swelling. Improvement was possible in mild cases of arthritis.

Uses in Osteoarthritis
Osteoarthritis (OA), also known as degenerative joint disease, is one of the most common forms of arthritis, affecting more than 32.5 million adults. It occurs when the cartilage that protects the joints wears down over time. Collagen supplements may help in rebuilding joints and reduce inflammation in osteoarthritis.

One study showed that when patients with knee osteoarthritis were given acetaminophen and collagen, significant improvements in their joint pain, function, and quality of life were reported. This was, however, a small study and included only 39 subjects.

 A systematic review focusing on osteoarthritis and cartilage repair found that collagen hydrolysate and undenatured collagen showed some potential as an valid alternative for managing osteoarthritis.

Uses in Rheumatoid Arthritis
Rheumatoid arthritis happens when the body’s immune system attacks healthy cells by mistake, causing painful swelling mainly in the hand, wrist, and knee joints. In Rheumatoid arthritis, the lining of the joint becomes inflamed, damaging the joint tissue. Collagen peptides can preserve cartilage and can stimulate chondrocyte cells to produce cartilage matrix, which helps in the cushioning and lubrication of the joints.