Men who spend more than six hours sitting each day are at higher risk of cancer, heart disease and diabetes, researchers have warned.
The negative effect of being sedentary is so profound that it holds true regardless of age, income, education and even weight.
Men who sat more reported a higher incidence of disease even if they had a similar body mass index compared with those who sat less.
Glued to the desk: Men who sat for more than six hours a day significantly increase their risk of cancer and diabetes
The research, carried out by Kansas State University, found a direct link between the amount of time people spend sitting and the likelihood of developing chronic conditions including cancer, heart disease and diabetes.
The study, published in the International Journal of Behavioral Nutrition and Physical Activity, followed 63,048 men aged 45 to 65, recording how long they sat each day as well as any ill health they experienced.
Daily sitting time was categorised as being less than four hours, four to six hours, six to eight hours, or more than eight hours.
The results showed that those who sat less than four hours per day were significantly less likely to suffer with chronic disease. Those sitting for at least six hours were significantly more likely to develop diabetes.
Even being physically active may not undo the damage of sitting for long periods
The findings are thought to be particularly relevant to those working in desk-based jobs as well as those who spend long periods of time driving.
Richard Rosenkranz, assistant professor of human nutrition who led the study, said: 'We saw a steady increase in risk of chronic diseases the more participants sat. The group sitting more than eight hours clearly had the highest risk.
'We know with very high confidence that more physically active people do better with regard to chronic disease compared with less physically active people, but we should also be looking at reducing sitting.
'A lot of office jobs that require long periods of sitting may be hazardous to your health because of inactivity and the low levels of energy expenditure.'
Despite the study focusing on men, researchers believe that the same results would be observed in women.
The new research is part of the 45 and Up Study, the largest long-term study of aging in Australia, involving more than 267,000 people.
Whilst researchers are confident that the evidence suggests inactivity is responsible for the increased risk of disease, they cannot be certain that too much sitting led to the development of diseases or whether the chronic diseases increased sitting time.
'It's a classic case of, "Which came first: The chicken or the egg?"' said Rosenkranz.
However, previous studies have observed similar results suggesting that sitting has a negative impact on health.
A 2007 study published by the University of Missouri found that sitting for prolonged periods of time was 'as bad for health as smoking' and just last year an Australian study demonstrated that adults who sat 11 or more hours per day had a 40 per cent increased risk of dying in the following three years compared with those who sat for fewer than four hours a day.
Read more: http://www.dailymail.co.uk/health/article-2281024/Sitting-desk-hours-day-dramatically-increases-risk-cancer-diabetes.html#ixzz2LSaCiz3P
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