The beneficial glucoraphanin compound is also found in Brussels sprouts and cabbage.

The body takes in glucoraphanin and turns it into another compound called sulforaphane, which appears to protect the joints.

The scientists are to start a short-term human study following on from their successful laboratory studies on mice.

They are asking 20 patients with severe arthritis to eat a daily dose of "super-rich" broccoli which has been cultivated to be extra rich in nutrients.

The volunteers will have two weeks on the broccoli diet before their knees are examined by surgeons.

Osteoarthritis is a degenerative condition that affects the joints. It is the most common type of arthritis in the UK, with around 1 million people visiting their doctor about it each year.

VoR's Brendan Cole spoke to Dr Rose Davidson, who is leading the research.