Sitting for long periods 'is bad for your health'

Recent research shows that sitting for long periods increases the risk of diabetes, heart disease and even death! The research, from the University of Leicester and published in the journal Diabetologia, combined the results of 18 studies and nearly 800,000 people. It found that prolonged sitting doubled the risk of diabetes and heart disease, and that the risk wasn't eliminated for those people who took regular exercise. Sitting is a low energy activity and it may be risky because it makes our bodies think we are in energy storage mode. This makes our bodies resistant to insulin (which mops up glucose), increasing the level of glucose in the blood and reducing levels of good cholesterols while increasing levels of bad ones. All of these changes increase the risk of obesity, diabetes and heart disease.


The research team, led by Dr Emma Wilmot from the Diabetes Group at the University of Leicester, says while going to the gym or pool after work is better than heading straight for the sofa, spending a long time sitting down remains bad for you. Each of the studies they assessed used different measures - for example more or less than 14 hours a week watching TV, or self-reported sitting time of less than three hours a day to more than eight.  The researchers said that while it is not possible to give an absolute limit for how much sedentary time is bad for you, it was clear that those who sat the most had a higher risk of diabetes, heart disease and death than those who sat the least. An Australian paper in the Archives of Internal Medicine of more than 200,000 people aged 45 or over found that those who sat for 11 or more hours a day had a 40% increase in risk of dying over the next three years, compared with those who sat for only four hours a day. The study took into account how healthy they were, as well as their levels of physical activity and weight.

Dr.Wilmot said......."If a worker sits at their desk all day then goes to the gym, while their colleague heads home to watch TV, then the gym-goer will have better health outcomes. But there is still a health risk because of the amount of sitting they do. Comparatively, the risk for a waiter who is on their feet all day is going to be a lot lower. People convince themselves they are living a healthy lifestyle, doing their 30 minutes of exercise a day. But they need to think about the other 23.5 hours."

Dr Wilmot said the study's message could help those at high risk of diabetes, such as obese people or those of South Asian ethnic origin, because it was an easy lifestyle change to make.

Prof Stuart Biddle, of Loughborough University, who also worked on the study, said: "There are many ways we can reduce our sitting time, such as breaking up long periods at the computer at work by placing our laptop on a filing cabinet. We can have standing meetings, we can walk during the lunch break, and we can look to reduce TV viewing in the evenings by seeking out less sedentary behaviours."

Dr Matthew Hobbs, head of research at Diabetes UK, said people should not be discouraged from exercising. He added: "What is clear is that anyone who spends lots of time sitting or lying down would benefit from replacing some of that time by standing or walking. Aside from any direct effect reducing the amount of time you spend sitting down may have, getting more physical activity is a great way of helping maintain a healthy weight, which is the best way of minimising your risk of Type 2 diabetes."

The solution.....What you can do to help will depend on your workplace. If you can, make sure you get up once an hour and walk briskly somewhere. Instead of emailing someone several desks away, speak to them in person. Stand up when taking a phone call – it uses more calories than sitting. Shun the lift and take the stairs. If you walk, you use four times as much energy as when you sit.

After work, try not to spend most of the evening watching television. Another Australian study, in the October issue of The British Journal of Sports Medicine, suggests that each hour of television watched after the age of 25 reduces life expectancy by 21.8 minutes.