Also called · chondroitin sulfate · proteoglycan · MSM · hyaluronic acid
What it is
By volume, articular cartilage is 70% water, 20% collagen, 8% proteoglycan and 2% cells.
Proteoglycan is a complex of a core protein with 100 or more chondroitin sulfate chains attached. The sugar side chains carry a negative charge that pulls in large amounts of water, and that hydrated gel is what gives cartilage its cushioning.
Chondroitin and glucosamine go into joint supplements because they are the raw material for that proteoglycan.
What it does
Cartilage does not heal itself
Articular cartilage has no blood vessels — it is fed only by joint fluid — and its regenerative capacity is very low. Even where damage does fill in, it is usually fibrocartilage, which never reaches the strength of the original hyaline cartilage, and degenerative joint disease progresses anyway.
Movement is how nutrition gets in
With no blood supply, diffusion alone is not enough. Load compresses the cartilage and squeezes water out; release lets it draw water back in. That compression-and-recovery cycle is the actual channel for exchanging tissue fluid. Appropriate exercise is itself a means of feeding the joint.
Read it alongside omega-3
The vicious cycle in osteoarthrosis runs on MMPs digesting healthy cartilage. Supplying raw material (chondroitin) and slowing the breakdown (ω3) act at two different points.
How to feed it
Cats get osteoarthrosis too, but the signs barely show. Watch whether they have stopped jumping up to high places.
Cartilage changes slowly. Give it at least 8 weeks of consistent feeding before judging.
What to watch for
Dogs kept on lifelong dietary restriction had a significantly lower incidence of hip osteoarthritis. (Smith et al., JAVMA 229(5), 2006) For joints, weight management has stronger evidence behind it than any supplement.
Growing large-breed dogs cannot regulate calcium absorption properly until around 10 months, so adding calcium raises rather than lowers the risk of joint disease.
Common questions
Where it regenerates it is mostly fibrocartilage, which never reaches the original strength. The goal is protecting what remains, not regrowing it.
The opposite. Cartilage is fed by compression and recovery. Regular exercise within a pain-free range is necessary.
Concerns this ingredient relates to
General nutrition information. It does not replace a diagnosis or a prescription. If your animal has a medical condition or is on medication, talk to your veterinarian first.