Blood markers observed in obese children — some as young as 7 — indicate their bodies host chronic inflammation, a driver of heart disease, and elevations in chemicals that promote blood clots.
The findings, reported today at the Endocrine Society annual meeting, in Washington, D.C., indicate that school-age plumpness can prove more than a social stigma. It may signal that youngsters are on their way to developing cardiovascular disease — and years earlier than even a generation ago.
Nelly Mauras, chief of endocrinology at Nemours Children’s Clinic in Jacksonville, Fla., and her colleagues sampled the blood of 202 children aged 7 to 18. Half were lean and came from healthy, lean families. The rest were obese, but not due to disease. Moreover, for inclusion in the new study, heavy kids could not have metabolic syndrome, a condition whose constellation of symptoms — from high blood pressure and high cholesterol to elevated blood sugar — marks individuals at risk of heart disease, stroke and diabetes.
With childhood obesity reaching epidemic proportions, Mauras’ group wanted to see whether extreme pudginess in youngsters posed the same potential heart risks as it does in adults. And her disturbing data now indicate that it indeed appears to.
C-reactive protein is a blood marker of systemic inflammation. Concentrations of this CRP were, on average, eight times higher in fat adolescents (those who had at least entered puberty) than lean kids their age. And for kids who had not yet entered puberty, CRP values were 12 times higher among the very overweight kids, compared to lean children their age. Not surprisingly, the heavy kids also had elevated levels of interleukin-6, a signaling molecule that stimulates the liver to make CRP.
Adiponectin is a hormone secreted by fat cells that possesses anti-inflammatory properties. Its blood level was lower in the heavy kids than their lean counterparts, Mauras reports, while values of PAI-1, a compound that inhibits the breakdown of blood clots, were notably higher in overweight youngsters. Heavy kids also had significantly higher blood concentrations of fibrinogen, a material that fosters blood clotting.
At a briefing for reporters, Mauras concluded that “the unhealthy consequences of excess body fat start very early in childhood.”
“That’s kind of scary, isn’t it?” asked Daniel Bessesen, chief of endocrinology at the University of Colorado Denver School of Medicine, after hearing the new findings. “We know that cardiovascular disease develops not over a year or two but over or 20 and 30 years. And if kids have that kind of biochemical profile when they’re 7 to 9 years of age, you wonder how our country’s going to deal with that 30 or 40 years from now. “
Indeed, will we be in the throes of a middle-age heart-disease and stroke epidemic? And if health care costs are almost beyond our means to manage now, how much worse will they become?
Mauras didn’t go into what’s behind childhood obesity, but plenty of nutritionists point to one growing problem: Too little exercise. Elementary and secondary schools around the country have been eliminating physical education programs. Aggravating the problem, those computers and video games that well-meaning parents have been bringing into our homes have been seducing kids into becoming couch potatoes.
Kids may not know the long term implications of a sedentary lifestyle. But we parents do — and need to get the nation’s youngsters up and moving again.
DelGiorno, C., . . . and N. Mauras. 2009. Simple Obesity without Features of the Metabolic Syndrome is Associated with Incrased Cardiovascular Risk Even before the Onset of Puberty in Children (Abst. OR18-4). Endocrine Society annual meeting: Washington, D.C. (June 12).
Note: To comment, Science News subscribing members must now establish a separate login relationship with Disqus. Click the Disqus icon below, enter your e-mail and click “forgot password” to reset your password. You may also log into Disqus using Facebook, Twitter or Google.