Psychologists suggest that while the problems may have initially been caused by a number of reasons - such as exposure to drugs and vaccinations, stress or toxic fumes - they are reactivated by everyday experiences that prompt the body to think it is still in the war situation. These could be something as simple as diesel fumes, smoke and fire.
The theory seeks to explain the wide range of symptoms and the fact that they persist more than eight years after the war ended. These two factors have baffled doctors looking for a single cause for the effects, and led to the idea of a Gulf War syndrome being challenged.
The Gulf War and Illness By Association is the result of almost two years of research by Dr Eamonn Ferguson and Dr Helen Cassaday of Nottingham University. It is published in the British Journal of Psychology. Dr Ferguson got the idea after hearing of the case of an American veteran who got a headache every time he smelt petrol. He had been a mechanic for 13 years before and never encountered any problems.
He said: "We are not saying that this is all in the mind. We are saying totally the opposite. The point is that these are responses that are learnt by the body, and bring about a range of genuine physical reactions." Dr Ferguson stresses that they are not attempting an explanation of all the problems which veterans complain of, such as apparent increase in cancers and liver disorders.
Sean Rusling, chairman of the National Gulf War Veterans' and Families' Association welcomed the report, saying: "This is the first independent, British paper that confirms that there is a Gulf War syndrome."