Sitting around for long periods raises the risk of developing type 2 diabetes, heart disease and premature death, even for people who have the amount of daily physical activity recommended by health professionals.

These were the conclusions of a large piece of research covering nearly 800,000 participants published in Diabetologia this week.

Emma Wilmot of the University of Leicester in the UK, and colleagues, pooled the results of 18 studies covering a total of 794,577 participants, and found people who sit for long periods have twice the risk of developing type 2 diabetes, heart disease and premature death compared to people who do not.

In a press statement issued over the weekend, they say their analysis found these links were still strong when they took into account the amount of moderate to vigorous physical activity people underwent; even those who met typical physical activity guidelines may still be harming their health by sitting around for long periods the rest of the time.

“The average adult spends 50-70% of their time sitting so the findings of this study have far reaching implications,” says Wilmot, a a Clinical Research Fellow in Diabetes and Endocrinology working at the Leicester Diabetes Centre, in Leicester General Hospital.

“By simply limiting the time that we spend sitting, we may be able to reduce our risk of diabetes, heart disease and death,” she urges.

Their analysis revealed that the most consistent links were between sitting and diabetes. Wilmot says this finding is particularly important for those groups who already have a higher risk for type 2 diabetes, such as people of South Asian descent, or with a family history of the disease.

The study is not the first to highlight the health risks of sitting for prolonged periods. For example earlier this year, researchers at Leicester’s departments of health sciences and cardiovascular science revealed how they found women who sit for most of the day have a greater risk for developing the metabolic symptoms that precede type 2 diabetes.

Another study found that interrupting prolonged periods of sitting with regular, two-minute breaks of light or moderate intensity activity like walking helped overweight people keep glucose and insulin levels under control.

This latest review also involved researchers from Loughborough University, where co-researcher Stuart Biddle is professor of physical activity and health. He suggests a number of ways people can reduce their sitting time, “such as breaking up long periods at the computer at work by placing our laptop on a filing cabinet.”

Another co-researcher, Melanie Davies, professor of diabetes medicine at Leicester, is a director of the National Institute for Health Research’s Leicester-Loughborough Diet, Lifestyle and Physical Activity Biomedical Research Unit, and is also honorary consultant at University Hospitals of Leicester. She says the paper also has an important message for health care professionals:

“… namely that being sedentary is common and dangerous for our long term health, particularly for diabetes and cardiovascular disease, and that this link appears to be over and above other lifestyle factors such as our diet and physical activity.”

Written by Catharine Paddock PhD