Can vitamin D prevent osteoarthritis?

A team of British researchers is mounting a major clinical trial to find out if taking Vitamin D can prevent osteoarthritis.

The trial of 600 people with osteoarthritis of the knee is being funded by a £500,000 grant (€728,300) from medical research charity the Arthritis Research Campaign (arc).

Osteoarthritis is a common and painful form of arthritis, affecting more than 1 million in the UK, many of them elderly. There is no cure, and current treatments are aimed merely at controlling pain.

Researchers at the Royal National Orthopaedic Hospital in Stanmore, Middlesex, and University College, London, are to assess whether simply adding Vitamin D to the diet through a tablet or supplement can stop the deterioration of osteoarthritis at the knee joint by preventing the destruction of cartilage, and reduce pain. Patients will be studied over a three-year period, and cartilage destruction measured by X-ray changes.

The research will be performed in collaboration with three other UK centres in Manchester, Norwich and Southampton.

Dr Richard Keen, the consultant rheumatologist at the RNOH in charge of the trial, said: "We hope that this study will bring real improvement to the lives of patients with osteoarthritis. We hope that by preventing the progression of the disease, patients will experience less joint pain from their arthritis."​

He added that supplementation with Vitamin D may also have other health-related benefits, which would also be assessed during the study period.

With an increasing number of older people, and improved life expectancy, the number of people with osteoarthritis is expected to increase dramatically over the next five years.

Earlier data from American studies has suggested that low levels of Vitamin D in the blood are associated with more wear and tear in the joint cartilage at the hip and knee. Joint replacement is currently the only option of alleviating the pain and stiffness of osteoarthritis.