News and EventsInactive adults face higher diabetes and heart disease risk
26th May 2009
Spending a lot of time on the couch or even at your desk can increase the risk of developing type 2 diabetes and cardiovascular disease, new research has found.
Research by the MRC Epidemiology Unit in Cambridge has shown that there is an association between time spent physically inactive, or sedentary, and increased levels of insulin in the blood, a predictor of diabetes risk. Their findings will appear in the journal Diabetes this week.
Dr Ulf Ekelund led a team of researchers in studying 376 middle-aged adults over more than five years from the Ely Study.
Each person’s heart rate was measured every minute while they were awake, then used to define a specific heart rate for each individual which corresponded to when that person was inactive. Scientists then calculated the number of minutes each person (166 men, 210 women) spent below their threshold over a four day period.
This information was analysed to see if there was an association between time spent sedentary and fasting plasma insulin levels, a measure of insulin resistance. The analysis showed that more time spent sedentary was associated with high insulin levels. People with elevated insulin levels are known to be much more likely to develop type 2 diabetes and cardiovascular disease.
"This is the first study demonstrating that sedentary living is associated with an adverse metabolic profile 5 to 6 years later suggesting a causal association between physical inactivity and insulin resistance. Furthermore, this relationship was independent of age, sex, adiposity and time spent physically active. The results may provide further evidence for the need of public health guidelines on decreasing sedentary behaviour, in addition to the established guidelines for physical activity in adults. Most people in modern society spend the majority of their awake time sedentary. We were interested to examine whether time spent sedentary could predict insulin resistance, a precursor for the metabolic syndrome and type 2 diabetes."
Dr Ulf Ekelund, MRC Epidemiology Unit
Results suggest the detrimental effect of sedentary living on insulin resistance was not dependent of adiposity (how fat a person is), smoking and the amount of time being physically active. Therefore, it is important to not only recommend people be more physically active but also that they reduce the amount of time they spend sitting.
The findings described in this article are taken from the following publication:
Helmerhorst HJF, Wijndaele K, Brage S, Wareham NJ, and Ekelund U. Objectively measured sedentary time may predict insulin resistance, independent of moderate and vigorous physical activity. Diabetes. 2009 May 26. Published online in advance of print.
doi: http://diabetes.diabetesjournals.org/content/early/2009/05/22/db08-1773.abstract
