ALEXANDRIA, Va., May 25 — The more hours of TV kids with type 1 diabetes watch, the less they are able to maintain good blood glucose control, according to a study published in the June issue of Diabetes Care.

The study by researchers in Norway found that the more television a child or adolescent watched, the higher the child’s average blood glucose level measured. For example, young people who watched less than one hour of television per day scored an average level of 8.2 percent on the HbA1c, a test that measures how well blood glucose is controlled over several months. Those who watched up to 2 hours daily scored 8.4 percent; up to 3 hours daily scored 8.7 percent; up to 4 hours daily scored 8.8 percent; and those who watched more than 4 hours of TV per day scored 9.5 percent on the A1C test. The ADA recommends keeping A1C levels at 7 percent or below.

The study noted that “children and adolescents in the United States spend more time watching television than any other activity except sleep,” and that they may even spend more time watching TV than going to school. With childhood obesity reaching epidemic proportions in the United States, sedentary activities such as television viewing are of particular concern. The American Academy of Pediatrics recommends children spend no more than two hours per day watching television, but 55 percent of the subjects in this study exceeded that level.

“It takes very little energy to sit in front of the tube,” said lead researcher Dr. Hanna D. Margeirsdottir, from the Department of Pediatrics at the Ullevaal University Hospital in Oslo. “The time spent watching TV could otherwise be spent on activities that require a lot more exertion and burn more calories. What’s more, TV viewing tends to be associated with snacking and may lead to poor eating habits. Obviously with childhood obesity levels being what they are these days, parents should be encouraging their children and teens to watch far less television and get out and move around a lot more.”