Crohn's Disease is a chronic inflammatory and painful bowel condition.

Sufferers tend to go through periods of remission in which there are no symptoms and relapses in which symptoms flare up.

The symptoms of Crohn's Disease vary according to whether it is in the small or large intestine but there are several common features which occur in most cases.

These include diarrhoea, abdominal pain, tenderness over the intestine, weight loss, fever and tiredness.

Other symptoms not involving the intestine include a sore mouth due to ulcers on the tongue or inside the cheek, painful, inflamed eyes and stiff or swollen joints.

Despite extensive and continuing research, the cause is still unknown but there are a number of factors which may play a part in the development of the disease.

The occurrence of Crohn's Disease in more than one member of a family is more common than would be expected and experts believe there is an hereditary tendency.

The risk to family members varies considerably between studies but is generally highest when a brother or sister is affected.

Studies have also shown a higher incidence among identical compared with non-identical twins.

There is no evidence that Crohn's disease is contagious, although some cases start after a patient has been suffering from gastroenteritis.

Researchers believe the disease is possibly started bacteria in the gut which release poisons. These attack the wall of the intestine and may cause the damage seen in Crohn's Disease.

If toxins were absorbed into the bloodstream, might explain symptoms which occur outside the intestine such as arthritis and skin lesions.

It is possible the breakdown of certain foods in large intestine plays a part Crohn's Disease and some patients find their symptoms improve if they avoid certain foods such as wheat, yeast milk. However, many other patients with the disease able to eat these foods.

There is a growing belief among medical experts that milk could be linked to condition.

Tim Page, from Wadhurst, has been battling to raise awareness of this potential link for several years, Mr Page's wife Sarah has suffered from the condition for more than ten years, which led to him setting up the Chronic Crohn's Campaign.

He said: "The evidence now starting to point towards a link with milk and it is important people made aware of it. I think message is finally starting get through."

The Food Standards Agency says the findings could change the way milk processed in an effort destroy a bacteria called mycobacterium avium subspecies paratuberculosis (Map).

The bacteria is tolerated by the vast majority people with no ill-effects but it could cause problems for people with a tendency towards Crohn's.

Research carried out by John Hermon-Taylor, professor of surgery at George's Hospital in London, shows Map is present the inflamed gut of the overwhelming majority people with Crohn's Disease.

The bug can sometimes transmitted to humans through infected cows' milk.

Prof Taylor says he is not recommending that people stop drinking milk but suggests people with the condition, or close relatives who may feel at risk, should try UHT milk instead.UHT involves higher pasteurisation temperatures making it more likely Map is destroyed in the process.

Lewes GP Michael Edwards has seen several cases of Crohn's Disease.

He said: "It is difficult know exactly what causes the condition but there is no doubt its effects can badly affect people's lives.

"The best we can do is try to help people alleviate the symptoms through controlling their diet and providing medication."