As far as exercise and diabetes are concerned, the more, the better.
Also, an additional 86 million are thought to have prediabetes; this describes a state where an individual's blood sugar level is higher than it should be, but not high enough to trigger a diabetes diagnosis. It is considered an early warning signal.
The risk factors for type 2 diabetes (the most common version of diabetes) are well known.
Being overweight or obese, high blood pressure, abnormal cholesterol and triglyceride levels, and inactivity are all known to play a substantial role. All of the above can be managed, at least in part, by exercise.
Exercise and diabetes: A fresh look
A new study, published this week in the journal Diabetologia, takes a deeper look at the role of exercise in the development of type 2 diabetes. It is the most in-depth study to examine exercise independent from other influential factors, such as diet. The conclusions from the report are clear:
"This research shows that some physical activity is good, but more is better."
Dr. Study co-author Soren Brage
Currently, physical activity guidelines in the U.S. and the United Kingdom recommend 150 minutes of moderate activity or 75 minutes of vigorous activity per week; this could include cycling, walking, or sports. However, according to the Centers for Disease Control and Prevention (CDC), fewer than 50 percent of American adults meet these recommendations.
The current study was a result of collaborative work between two institutions - University College London and the University of Cambridge, both of which are based in the U.K. Data from more than 1 million people was collated. In all, the team analyzed 23 studies from the U.S., Asia, Australia, and Europe.
Thanks to the vast amount of information available to them, the investigators were able to strip out the effects of exercise and examine them independently of other behavioral factors, such as diet and smoking. This is in contrast to earlier work that has not been able to isolate the impact of physical activity alone.
The researchers found that any exercise is beneficial in staving off diabetes, but individuals who exceeded the 150 minute recommendation saw the greatest benefits.
'More is better'
According to the analysis, cycling or walking briskly for 150 minutes each week cuts the risk of developing type 2 diabetes by up to 26 percent.
Those who exercise moderately or vigorously for an hour each day reduced their risk by 40 percent. At the other end of the scale, for those who did not manage to reach the 150 minute target, any amount of physical activity they carried out still reduced the risk of type 2 diabetes, but to a lesser extent.
"Our results suggest a major potential for physical activity to slow down or reverse the global increase in type 2 diabetes and should prove useful for health impact modeling, which frequently forms part of the evidence base for policy decisions."
Lead author Andrea Smith
As mentioned, exercise has long been known to reduce the risk of developing type 2 diabetes; however, now we have a clearer picture of the exact figures behind this effect. As Dr. Brage says:
"These new results add more detail to our understanding of how changes in the levels of physical activity across populations could impact the incidence of disease. They also lend support to policies to increase physical activity at all levels. This means building environments that make physical activity part of everyday life."