It's likely to cause controversy among the medical profession, but Sarah Freeman meets two experts determined to prove that loneliness is just as harmful as smoking, obesity and lack of exercise.
Medical breakthroughs over the last half a century or so have taught us many things.
We know eating fatty foods causes blocked arteries which in turn lead to heart attacks, we understand that a 20-a day smoking habit increases the risk of lung canc
er and the link between obesity and diabetes has never been more clear.
However, according to a Yorkshire academic and a London psychoanalyst, some of the greatest killers of our age are not only going unnoticed, but unfortunately can't be cured by a nicotine patch or better diet.
"We are all familiar with information about the dangers of poor diet, smoking and a sedentary lifestyle," says Ilkley philosopher David Corfield, who has been researching what makes people ill with psychoanalyst and fellow Cambridge University graduate Darian Leader.
"But often, the context of an illness can provide vital clues as to why people fall ill, and this leads to important questions which the medical profession need to answer.
"If two men of the same age have heart attacks which result in equal damage, why is the man who is single and depressed more likely to die of heart disease within the following year than the man who is married and not depressed?
"How is it possible that some asthma sufferers have found their lungs function better after they have started writing about their condition, and why is it that research shows social isolation can be just as devastating to one's health as smoking and lack of exercise?"
The claims made by Leader and Corfield might sound like the musings of New Age alternative therapists, but an increasing amount of scientific research supports their theories. Earlier this month researchers in Chicago published findings which suggested lonely individuals are twice as likely to be diagnosed with Alzheimer's disease as those who trust in a close circle of family and friends.
The news was widely seen as an important breakthrough in understanding the condition, but the results barely warranted more than an approving nod from Leader and Corfield, who have, over the years, trawled through piles of case studies on various diseases which have all pointed to similar conclusions.
"Moments of separation and loss are especially significant in terms of people's health," says Leader. "When an important relationship breaks down, it is inevitably an emotionally difficult time, but the problems come when people can't find a way of processing and channelling that loss. That's when some of the body's internal systems may be compromised.
"It's important not to generalise, but for example, there has been research which has suggested that whose who find it difficult to express emotions are more at risk of developing cancer, and those who display signs of anger and hostility have been identified as likely victims of heart attacks."
What's needed, they say, is a less black and white approach to medical diagnoses and treatment, and a greater acceptance that grey areas not only exist, but that a patient's background and life history may shed light on their symptoms.
"Most people would agree that one's mental state affects physical wellbeing, even if it's just acknowledging that nerves before a job interview can give you a stomach ache," says Leader. "However, while research shows our brain is in constant communication with the immune system, it is still often assumed that each illness is a well-defined entity that has a single specific cause and a single specific cure
"The medical profession has become increasingly bureaucratic, and there isn't any place for listening to the narrative story of the human life.
"The average consultation between a patient and a GP lasts six to eight minutes, a patient speaks for just 23 seconds before being interrupted, and half of all doctors and patients disagree on the diagnosis of their illness. So surely it's time to start looking at alternatives."
While medical developments have vastly increased the numbers who survive major surgery and conditions once thought to be fatal, according to Leader they have overshadowed once basic medical practices, which are now seen as having no place in the world of keyhole surgery, pacemakers and triple heart bypasses.
"You only have to look at the area of psychosomatic illness to see that there may be lessons to be learned from history," he says.
"Now it's an umbrella term to dismiss conditions seen as trivial, but in the 1930s it was used to describe a specific approach to treating a patient which involved looking at what else was going on in their life which might have contributed to the physical symptoms.
"In the 1950s, people's heads were turned by various discoveries and breakthroughs, which is understandable, but in the excitement the psychology of medicine seems to have got lost.
"Of course it would be a huge step forward if we could say people who are lonely will develop cancer, but those simple correlations don't exist, and generalisations aren't of much help.
"However, it is about being open-minded. If a study showed that only one in a hundred women experienced a worsening of, say, her rheumatoid arthritis after an argument with her children, it shouldn't be dismissed, because there still may be lessons which can be learned."
Leader and Corfield cite the increasing numbers of people seeking alternative therapies as a sign of growing acceptance that traditional medicine doesn't necessarily know it all.
However, with no easy remedy to the problem of GP surgeries which are short of time and money, they also add that patients must take more responsibility for their own illnesses.
"It's about making people think more about what may be contributing factors, and look at their medical problem within the context of their own life," adds Leader. "There are so many people who, say, fall ill on the same date and often with the same illness year after year, but dismiss it as just coincidence.
"Clearly in some cases it is nothing more than that, but there is also research to suggest that a separation or loss in the past that we think we have got over returns to affect us. It's called 'anniversary symptoms'.
"There is a case of a man whose family had been murdered in the concentration camps during the Second World War.
"The only known anniversary for any of the deaths he could be sure about was that of his brother, and it was always on this day in the year that his multiple sclerosis would worsen.
"We both know that there will be psychologists who don't think our conclusions go far enough, and some GPs would think they go too far. But if it provokes a debate about what really makes us ill, then that has to be a good thing."
Why Do People Get Ill? by Darian Leader and David Corfield is published by Hamish Hamilton, and is available for £16.99 plus £1.95 p&p from the Yorkshire Post Bookshop on 0800 0153232 or online at www. yorkshirepostbook shop.co.uk
