Posted on October 25, 2001 at 9:35 a.m.

BIRMINGHAM, AL — Healthy teenagers grow resistant to insulin in much the same way as people with type 2 diabetes, according to a new study done by researchers at UAB (University of Alabama at Birmingham) and the Keck School of Medicine at the University of Southern California.

At the onset of puberty, cells in children’s bodies grow less responsive to insulin, a natural hormone that helps cells convert sugar from food into energy, according to a paper published in the November issue of the journal Diabetes. The findings of the study, the first to track sensitivity and response to insulin from childhood through young adulthood, could aid physicians in the prevention of type 2 diabetes, an increasingly common health problem among young adults.

“In most teens, insulin resistance disappears after the end of puberty, and normal metabolism resumes,” says Barbara Gower, Ph.D., assistant professor of nutrition sciences at UAB and a study co-author. “But we speculate that in others, prolonged insulin resistance and associated stress on the pancreas ultimately lead to the development of type 2 diabetes.”

Gower and co-author Michael Goran, Ph.D., professor of preventive medicine at the Keck School at USC, studied 60 ethnically diverse children at UAB beginning at about age nine. Sensitivity to insulin dropped by 32 percent as the children reached the middle stages of puberty.

“The theory is that lowered insulin sensitivity is a beneficial thing that switches on growth during puberty,” Goran says. “The tumultuous transformations and growth spurts of the teen years might naturally require the body to produce additional insulin to drive growth and tissue deposition.”

For reasons still not understood, some teens do not recover insulin sensitivity as adults. This can stress the pancreas, initially requiring it to produce more insulin, but ultimately leading to pancreatic failure and type 2 diabetes. Gower and Goran suggest that it will be necessary to finds ways to ensure that sensitivity to insulin recovers by the end of puberty, before pancreatic function declines.

“More importantly, dietary and physical activity interventions should be explored for decreasing body fat and increasing insulin sensitivity prior to and during puberty,” Goran says.

According to the American Diabetes Association, type 2 diabetes affects more than 15 million adult Americans. Complications may include early heart disease, kidney problems, vision loss and limb amputations. Cases are increasing in adults and children. As many as 85 percent of such children are overweight and most are diagnosed in middle-to-late puberty.

The study was supported by the National Institute of Child Health and Development, the National Institute of Aging, and a UAB General Clinical Research Center grant.