Scientists hope adding vitamin D to the diet could help prevent one of the most common and painful forms of arthritis.
Osteoarthritis affects more than a million people in the UK, many of them elderly.
There is currently no cure and all doctors can do is control pain and keep patients active and mobile.
With the growing number of elderly people and better life expectancy, the number of people with osteoarthritis is expected to soar over the next five years.
Source BBC News