Brain Structure Changes Can Lead to Obesity

University of Washington investigators say that humans and rats are two species in which structural changes affecting the brain can lead to the development of obesity. As such, the unsuspecting rodents are used as a proxy for humans, with researchers trying to figure out how to stop the condition.

The situation nowadays is pretty bad, when it comes to obesity, because the developed world is experiencing the largest outbreak of the condition in recorded history. The United States is worst-off, with two thirds of its population being either overweight, or obese.

As such, finding ways of addressing this issue could lead to diminished healthcare costs, as well as an improved quality of life for patients. In addition, the incidence of conditions associated with obesity, such as cardiovascular problems and diabetes, would decrease considerably as well.

In the new investigation, scientists were able to find early and lasting injuries to a part of the hypothalamus in mice and rats that were bred specifically to develop obesity. They say that similar damage is also visible in the human brain, in exactly the same area.

“Obese individuals are biologically defending their elevated body weight,” UW professor of medicine and study leader Dr. Michael W. Schwartz explains, as quoted by PsychCentral.

“To explain a biologically elevated body weight ‘set-point,’ investigators in the field have speculated about the existence of fundamental changes to brain neurocircuits that control energy balance,” he adds.

According to the investigator, no other study has ever provided this type of direct evidence of a brain change occurring when it comes to obesity. The study is also interesting because it found the same thing in two different species.

Still, the researchers admit that they have yet to demonstrate a causal relationship between the injuries affecting hypothalamic neurons and an innate bodily mechanism for defending increased bodyweight.

This type of demonstration “comes next. But this amounts to solid evidence of a change affecting the key hypothalamic area for body weight control with the potential to explain the problem,” Schwartz explains.

Details of the new investigation appear in a paper called “Obesity Is Associated with Hypothalamic Injury in Rodents and Humans,” which is published in the January 3 issue of the esteemed Journal of Clinical Investigation.