High-calorie, low-fiber diets can promote hormonal imbalances that lead children to overeat, one researcher warns.

Current food-manufacturing practices create a "toxic environment" that dooms children to being overweight, said Dr. Robert Lustig, professor of clinical pediatrics at the University of California, San Francisco, Children's Hospital.

He conducted a large-scale review of obesity research. His findings were published in the August issue of the journal Nature Clinical Practice Endocrinology & Metabolism.

"Our current Western food environment has become highly 'insulinogenic,' as demonstrated by its increased energy density, high fat content, high glycemic index, increased fructose composition, decreased fiber, and decreased dairy content," Lustig noted.

"In particular, fructose (too much) and fiber (not enough) appear to be cornerstones of the obesity epidemic through their effects on insulin," Lustig said.

He noted that obesity is now the most commonly-diagnosed childhood ailment in the United States. Diseases previously only seen in adults, such as type 2 diabetes, are now becoming widespread in children.

Children who are obese are often ridiculed and socially isolated, which puts them at risk for depression and other mental health problems, Lustig said.

He urged societal action to correct the problem, noting that children can't be blamed for being overweight or expected to take personal responsibility for poor dietary habits when they're surrounded by unhealthy foods.