A study recently published in the New England Journal of Medicine offers hope to overweight children everywhere. It found that if obese or overweight children slim down by the time they become adult, they also reduce their health risks dramatically.

The study results aren't all good news. Nearly 65% of the children in the study who were overweight or obese did grow up to become obese adults. And those that did had a variety of health problems as young adults not seen in their slimmer counterparts.

Many studies have shown that heavier children face an increased risk of heart disease and diabetes as adults. But few if any have looked at what happens if these children shed the excess pounds.

But the study did find that children who had addressed their weight problem before becoming an adult were faring just as well as the slimmer children were.

Finnish and American researchers looked at four previous studies from the U.S., Finland and Australia that had tracked children for an average of 23 years, to see what effect slimming down had on children's health in later life.

The study's bad news starts with the finding that heavy children tend to grow up into heavy adults: while only 15% of the normal-weight children became obese adults, nearly 65% of the overweight or obese children and 82% of the obese children did so.

The researchers then compared certain health measurements of these children in adulthood. Some highlights were that obese adults who were heavy in childhood had a 5.4 fold increased risk of diabetes, a 2.7 fold higher risk of high blood pressure and a 1.7 fold increase in the risk of atherosclerosis (narrowed arteries) than the non-obese adults who had been normal weight children.

Yet the non-obese adults who had been heavy youngsters but later slimmed down had no higher risk of these conditions than the normal-weight children who became non-obese adults. In other words, losing the extra weight eliminated the associated health risks.

Many studies have shown that heavier children face an increased risk of heart disease and diabetes as adults. But few if any have looked at what happens if these children shed the excess pounds.

Two presentations at the American Heart Association's 2011 Scientific Sessions highlight the nation's growing obesity problem. One estimates that 72% of U.S. men and 63% of women are currently overweight or obese and that these numbers will rise to 83% and 72% in 2020 if current trends continue. The other found that 35% of the 12-to-19- year-olds studied were already overweight or obese and suggests that this is a primary reason that heart disease is now on the rise in adults 35 to 44 years old.

And while no one seems to have all the answers to these problems, the Finnish/American study suggests there is a real possibility of improvement.

An article on the Finnish/American study appears in the New England Journal of Medicine.