GAINESVILLE, Fla.---Most of us have experienced eating and eating until suddenly we're so stuffed we can hardly waddle from the table to the couch.
Now for the first time, scientists at the University of Florida and the University of Texas have pinpointed the time it takes for the human brain to signal it's full and which areas of the brain are involved in eating. As it turns out, 10 minutes is generally all that separates nutritiously satisfied from excessively gorged.
That knowledge could be key in the diagnosis and treatment of obesity and associated conditions.
By mapping changes in blood flow and oxygenation using a technique called functional magnetic resonance imaging, termed fMRI, the researchers were able to record activity changes in the neurons to determine where in the brain, and more important, when the physiological reactions to food occur, the scientists report in the June 29 issue of Nature.
"The hypothalamus has been known for many years as being related to the regulation of eating, but this is the first study in humans able to directly demonstrate that it undergoes dynamic and physiologic changes as a result," said primary investigator Yijun Liu, an assistant professor in the UF College of Medicine's department of psychiatry.
"Most importantly, using a noninvasive technique, this study determined there was a connection between the changes that occur in the human brain after eating and the traditional biochemical indicators in the body, which are increases in the levels of glucose and insulin in the blood," said Liu, who also is affiliated with the Evelyn F. and William L. McKnight Brain Institute of the University of Florida.
The findings could help scientists further comprehend how the brain responds to eating and food. That has important implications in better understanding the brain mechanisms involved in the development of obesity and obesity-related diabetes, and for devising and testing medications
Contact: Paula Rausch
University of Florida