Zinc-rich foods, including seafood, cocoa and chicken, could be causing the painful condition osteoarthritis, Daily Mail reports. 

Cartilage can be destroyed by molecular changes involved in processing zinc, a new Korean study has found.

When the cartilage breaks down in osteoarthritis, the bones rub together, causing pain, swelling, and stiffness.

However, there has been a lack of effective therapies for the disease because before now the underlying molecular causes have been unclear.

But a new study revealed that osteoarthritis-related tissue damage is caused by a molecular pathway that is involved in regulating and responding to zinc levels inside of cartilage cells.

A protein called ZIP8 transports zinc inside these cells, setting off a cascade of molecular events that result in the destruction of cartilage tissue in mice.

As a result, reducing zinc levels could lead to a new generation of therapies for osteoarthritis.

Because matrix-degrading enzymes require zinc to function, researchers suspected that zinc levels inside of cartilage cells may play a role in osteoarthritis.

'We are hopeful that this research will lead to the discovery and rapid development of novel drugs to suppress the progression of this debilitating disease,' the researchers said.