How long have you been sitting today? Here's one more reason that you should get up and move around once in a while.
A new study in the journal Diabetologia suggests that reducing your sitting time is more important in lowering your risk of diabetes than exercise. This is just the latest in a string of research suggesting that moving around helps your health. But the new results should not replace standard recommendations for exercise, and more research is required to understand the reasons for the findings, said lead study author Joseph Henson.
"It looks as if just sitting for long periods of time has a real negative impact upon overall health," Henson said.
Why study diabetes
A chronic illness, diabetes reflects a problem in the body with the hormone insulin, which regulates blood sugar. The condition happens when the body can't use the insulin that it produces effectively, or when the pancreas doesn't produce enough of the hormone.
Henson, of the Diabetes Research Unit at the University of Leicester, wanted to explore this topic because of the increasing prevalence of diabetes worldwide. Nearly 350 million people around the globe have diabetes, according to the World Health Organization, and deaths from diabetes are expected to increase by two-thirds between 2008 and 2030.
"The increase in diabetes has been due to the fact that people have generally just gotten larger," Henson said. So as obesity has increased so has the prevalence of diabetes."
The trend is obvious in the United States. The number of people with diagnosed diabetes went from 5.6 million to 20.9 million from 1980 to 2010, according to the Centers for Disease Control and Prevention. This disease is also a huge driver of health care costs in the U.S., according to the American Diabetes Association.
This study looked specifically at people at risk of type II diabetes in the United Kingdom. Participants came from two diabetes prevention programs.
Researchers put accelerometers on 878 patients to see how much they moved or didn't move, monitoring when they took breaks from sitting down. They wore these devices on their hips for at least seven consecutive days, during waking hours, the study said.
The study found that sedentary time was associated with worse outcomes in "bad" HDL cholesterol, 2 h glucose and triacylglycerol, which are all indicators of metabolic and cardiovascular health.
Perhaps surprisingly, time spent sitting - not time spent exercising - was the factor most strongly associated with health outcomes examined in the study. Why? Henson said there may be a specific enzyme that responds differently when people are sitting, compared to when they exercise, but more research is needed.
Data from the study suggests that reducing time sitting by 90 minutes during the course of the day significantly lowers the risk of diabetes, Henson said.
This was not a controlled study, meaning the study authors did not deliberately prescribe a group a certain amount of physical activity and compare outcomes with another group who sat the whole time. A rigorous experimental design is necessary to more conclusively draw connections between behaviors and disease risk.
As has been demonstrated in other studies, taking breaks from sitting appears to be associated with better health indicators.
The participants in this study were already at risk for diabetes, so in a person who does not have a predetermined risk, "trying to move for 5 minutes every hour seems right," Henson said.