Itâ€™s nothing new in the scientific community that there is more than just lifestyle choices that come into play when determiningÂ who is fat and who is thin. There are various biological factors that often play a significant role in peopleâ€™s weight.
While the most commonly known biological factor for oneâ€™s weight is varying resting metabolisms, there are also neurological factors. The latest findings assert that obese people have a tendency to lack impulse control when it comes to food.
Researchers compared the brain scans of thin people to obese people when both looked at pictures of high-calorie foods. What they found was that there was an increased activity in a region of the brain used for impulse control with thin people, butÂ there wasnâ€™t so much activity in the region of the obese people.
“I think there may be biological reasons why people can’t necessarily control their desire for food,” said Robert Sherwin of Yale University School of Medicine in Connecticut, who worked on the study.
With obesity effecting around a third of our population, researchers are trying to better understand the reasons beyond simple inactivity and bad food choices.
There were 14 people in the study, with nine who were thin and five obese. Everyone underwent brain scans two hours after they ate. The researchers manipulated their blood sugar, testing the subjects when they had normal and low blood sugar levels.
When blood sugar levels were low, regions in the brain called the insula and striatum associated with rewards are activated, which give the signal to want to eat. The prefrontal cortex normally dampens signals to eat, but it wasnâ€™t as effective at stopping signals to eat.
The key finding was that it was particularly true with the obese subjects. Even when blood sugar levels were normal, the thin participants showed more activity in the prefrontal cortex, which reduced reward activity in the brain.
“There is a controller — a higher function that controls your reward centers. That controller is deficient in people with obesity. They don’t activate that system,” said Sherwin.
While Sherwin admits larger studies are need to confirm these findings, his study still strongly suggests that obese people are less able to shut off food cravings in the brain.
September 28th, 2011