CHICAGO - Diabetic children who spent the most time glued to the TV had a tougher time controlling their blood sugar, according to a Norwegian study.

The findings, based on a study of children with Type 1 diabetes, lend support to the American Academy of Pediatrics' advice that children should watch no more than two hours of TV daily, said the study's author Dr. Hanna Margeirsdottir of the University of Oslo.

Type 1 diabetes is the less common form of the disease and used to be called juvenile diabetes. It is not related to obesity and is caused when the body cannot make insulin, which converts sugar from food into energy. People with Type 1 must take insulin daily and regulate their blood-sugar levels.

While TV-viewing is often accompanied by snacking, the researchers didn't examine diet or physical activity. But the results suggest that encouraging children with Type 1 diabetes to watch less television may be important for improved blood glucose control and better health outcomes.

But other experts said the study also might suggest something else - perhaps diabetic children who have consistently high blood-sugar levels could feel too sick to do much besides watch TV, said Jill Weissburg-Benchell, a psychologist and diabetes educator at Children's Memorial Hospital in Chicago.

“It's very clear that there is a relationship. Now the question is what underlies that relationship,” she said.

In Norway, about 25,000 people have Type 1 diabetes. In the United States, 3 million have the condition with 30 million people afflicted worldwide. The study involved 538 children with an average age of 13.

The study evaluated results of a routine test that measured average blood-sugar control over three months. There was a continuous increase in the level of blood sugar with every hour of TV watched, rising to the highest level for those who watched at least four hours daily.

The results didn't surprise Chicago diabetes educator Monica Joyce, who founded a basketball camp for diabetic children.

Campers typically are asked how much TV they watch and how activity can improve their blood sugar, Joyce said.

If the researchers' theory is right, turning off the TV could be added to a list of remedies “that are very low-cost to the health care system,” said Dr. Francine Kaufman, head of a diabetes program at Children's Hospital in Los Angeles.

“This has got to be the social norm that it's just not acceptable for kids to be baby-sat by TV,” she said.

Results of the Oslo research will appear in the June edition of the journal Diabetes Care.