If you’ve noticed you’re getting heavier, you had better get your weight under control before its too late. A recent study suggests that the longer someone is obese or overweight, the more likely they will regain the weight they work so hard to lose. The researchers said the possibility of irreversible obesity stresses the importance of intervention in childhood to prevent a lifetime of obesity.
The challenge of permanent weight loss
Joint research between the University of Michigan and the Argentina-based National Council of Science and Technology (CONICET) offers new insight on the daunting challenge to losing weight and keeping it off. Using a unique strain of genetically programmable mice, scientists have discovered that obesity, if allowed to continue over time, reprograms the body to seek a permanent heavier “normal weight.”
Flipping the hunger control switch
The study, published in the Journal of Clinical Investigation, created a new model for tracking obesity by manipulating a genetic switch that controls hunger in laboratory mice.
Mice with the hunger control gene activated after weaning did not overeat and maintained normal weight. Mice kept at a normal weight after weaning by strict dieting continued to maintain normal weight without dieting, even after their genetic hunger control switch was turned on. Mice induced with early-onset obesity via overfeeding could never return to a normal weight after their switch was flipped, no matter how strenuous the diet and exercise.
Is regaining weight unavoidable?
“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 lead author Dr. Malcolm J. Low, a professor of molecular and integrative physiology and internal medicine at the University of Michigan. “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.”
If obesity is indeed a self-perpetuating, irreversible condition, it doesn’t bode well for the estimated 43 million children worldwide under 5 years old who are already obese. The findings could be particularly discouraging for the 500 million obese adults worldwide.
Reset to a healthy weight?
According to Low, more research is needed to figure out why the body resets itself to be heavy. Perhaps studies should be done to see if it is possible to re-reset the body with a strictly-enforced, prolonged period of healthy weight.
The search for clues could start with the fact that slow, steady weight loss is more effective than rapid weight loss. Slow weight loss, recommended at about one to two pounds a week, allows metabolism and energy levels to stay balanced as the pounds drop off. Rapid weight loss slows metabolism and makes losing weight harder to continue.
Humans aren’t mice
Slower weight loss also helps the body cope with diet and lifestyle changes and avoids health problems associated with rapid weight loss, such as nutrition deficiencies, dehydration and loss of lean muscle mass.
Although the study suggests that prolonged obesity may be irreversible in mice, one can’t assume the same is true for humans. Enough success stories exist to suggest that permanent weight loss is within reach for anyone, with permanent motivation and discipline.