In yet another study to underscore the importance of tackling childhood obesity early, new research suggests that the longer a person remains obese, the more “irreversible” the condition becomes.
The reason? Over time, a constant state of obesity was observed to reset the ‘normal’ body weight set point to become permanently elevated, researchers said, which could explain why dieters often experience difficulty keeping weight off through diet and exercise alone.
Published last week in the online edition of the Journal of Clinical Investigation, the new findings raises questions about the long-term success rate of extreme diets and weight loss programs, said researchers, who cited popular US reality TV show The Biggest Loser as an example of a possibly misguided diet strategy.
The study was carried out jointly by the University of Michigan in the US and the Argentina-based National Council of Science and Technology.
"Somewhere along the way, if obesity is allowed to continue, the body appears to flip a switch that re-programs to a heavier set weight," said senior US author Malcolm J. Low in a statement.
"The exact mechanisms that cause this shift are still unknown and require much further study that will help us better understand why the regaining of weight seems almost unavoidable."
'Elevated body weight set point'
The elevated body weight set point was observed in what the researchers describe as a pioneering mouse model where scientists were able to flip a genetic switch that controlled hunger at different stages.
When scientists flipped on the hunger switch -- which worked by preventing the mice from overeating -- those that were put on a calorie-restricted diet in early adulthood were observed to maintain a normal weight.
But when the same was done for mice with the earliest onset of obesity, despite the reduction in food intake and increased activity, researchers say the animals never completely returned to a normal weight.
"Our model demonstrates that obesity is in part a self-perpetuating disorder and the results further emphasize the importance of early intervention in childhood to try to prevent the condition whose effects can last a lifetime," Low said.
Meanwhile, the Centers for Disease Control and Prevention recommends fostering healthy eating habits by serving reasonably sized portions, limiting sugar-sweetened beverages, and encouraging physical activity like playing tag, jump rope, soccer and swimming.
Moreover, the Mayo Clinic also advises that one of the best ways of preventing childhood obesity is for parents to serve as role models and eat healthfully as well.