More TV time may raise Type 2 diabetes risk

While sitting less wasn’t a goal, watching less TV was discussed briefly in the lifestyle curriculum and encouraged.

Emphasize sitting less in lifestyle programs, researchers suggest

Each hour spent watching TV each day increases the risk of developing Type 2 diabetes among overweight adults, a U.S. study suggests.

The study in Wednesday's issue of the journal Diabetologia was based on data from 3,234 overweight American adults who participated in a randomized trial aimed at preventing or delaying Type 2 diabetes among those at high risk of the disease with medication or lifestyle changes.

Sedentary behaviour — watching TV, computer use, or sitting during commutes and at work — is considered a potential risk factor for Type 2 diabetes, regardless of physical activity.

The goals were to achieve a seven per cent weight loss and at least 150 minutes per week of moderate intensity activity, such as brisk walking.

Before the lifestyle changes were introduced, those in the drug, lifestyle and placebo groups all spent about 140 minutes a day in front of the set. 

While sitting less wasn't a goal, watching less TV was discussed briefly in the lifestyle curriculum and encouraged.  

Over the average of three years of follow-up, TV time fell by 22 minutes in the lifestyle group, eight minutes in the placebo group and three minutes in the drug group, Dr. Bonny Rockette-Wagner from the University of Pittsburgh and her co-authors found.

"Combining all participants together, there was a significantly increased risk of developing diabetes with increased television watching (3.4 per cent per hour spent watching television), after controlling for age, sex, treatment and leisure physical activity," they concluded.

"Additional emphasis on reducing sedentary behaviours in lifestyle intervention programmes that are already focused on increasing leisure physical activity levels is merited."

The trial was funded by the U.S. National Institute of Diabetes and Digestive and Kidney Diseases. One of the authors has a financial interest in a company that develops online behaviour change programs. 


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