"There were two things going on here. First, the earlier you are exposed to obesity, the earlier we may see the onset of complications including type II diabetes, cardiovascular disease, metabolic syndrome and cancer. That makes sense: these complications don't happen overnight, and the earlier you start the ball rolling, the earlier and more likely you are to see early morbidity and mortality from them. But then it looks like independent of this increased-exposure effect, kids' maturing bodies may be especially vulnerable to the detrimental health effects of obesity. Early exposure can make you much more predisposed to complications than might exposure once the body is done maturing. It may be that childhood obesity changes the way the whole metabolism is working -- and changes it during a critical developmental time frame," says Kristen Nadeau, MD, investigator at the CU Cancer Center, associate professor of Pediatric Endocrinology at the CU School of Medicine, and the paper's senior author.

Previous studies have shown the intuitive causal chain of childhood obesity leading to adult obesity, which in turn leads to complications, but recent evidence shows that childhood obesity may also create these effects independent of adult obesity. Childhood obesity may itself be enough to cause outcomes including metabolic syndrome, cardiovascular disease, type 2 diabetes and its associated cardiovascular, retinal and renal complications, nonalcoholic fatty liver disease, obstructive sleep apnea, polycystic ovarian syndrome, infertility, asthma, orthopedic complications, psychiatric disease, and increased rates of cancer, among others.