Evidence found for brain injury in diet-induced obesity

By Roberta Wilkes

(Medical Xpress) -- The first evidence, reported today, of structural changes in the brains of rodents and humans with diet-induced obesity may help explain one of the most vexing problems of body weight control.

Dr. Michael W. Schwartz, professor of medicine at the University of Washington, is the senior author of the study.

The well-established tendency to regain weight lost through dieting and exercise, as re-confirmed by a prominent Australian study earlier this year, is the single largest obstacle to successful . Body weight is controlled by complex interactions between hormones and in a brain area known as the . These interactions influence appetite and and , in most obese people, conspire to prevent permanent weight loss.

“Obese individuals,” said Schwartz, “are biologically defending their elevated body weight.” The mechanism for this phenomenon is the object of intense investigation by neuroendocrinologists.

Schwartz said, “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. Our findings are the first to offer direct evidence of such a structural change, and they include evidence in humans as well as in mice and rats.”

His group studied the results of a high-fat diet in the brains of mice and rats that were bred to become obese on this diet. They found evidence of very early and lasting injury to a specific part of the hypothalamus in these animals. Using brain imaging, they also found signs of similar damage in the same area of the brain in obese humans.  

“We did not prove cause and effect between the hypothalamic neuron injury and defense of elevated body weight - that 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,” said Schwartz.

Dr. Josh Thaler, assistant professor of medicine, is the first author of the paper, which will be published in the January 3 issue of Journal of Clinical Investigation and is entitled “Obesity Is Associated with Hypothalamic Injury in Rodents and Humans.” Co-authors include Ellen A. Schur, Stephan J. Guyenet, Bang H. Hwang, Xiaolin Zhao, David A. Sarruf, T. Nguyen, Jonathan Fischer, Miles. E. Matsen, Brente E. Wisse, Gregory Morton , Denis G. Baskin,  and their colleagues in the UW Department of Radiology and at Yale and the University of Cincinnati.

More information: Read the Journal of Clinical Investigation paper: www.jci.org/articles/view/59660

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kochevnik
1 / 5 (1) Dec 29, 2011
Hemp seeds help regulate cravings, and are rich in omega3 for the brain.
rawa1
1 / 5 (1) Dec 29, 2011
There is some evidence for breatharians (Henri Monfort), who can survive at very subtle diet. So it's possible, under heavy diet the organisms switches into regime, which requires very low food income and under such a situation even normal food regime leads into obesity again.

http://en.wikiped...atharian
rawa1
1 / 5 (1) Dec 29, 2011
I don't understand, why it's so impossible to test this guy in some medical peer-reviewed study. It's similar case like the cold fusion - all people are parroting, it's impossible, but no one is willing to check it.

http://nourriture....free.fr