By Robbie Owens

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NORTH TEXAS (CBS11) – It only takes a glance to realize that Craig Thompson is not the man he once was… the man he was when he weighed some 400 pounds. Now, he flies drones and pilots planes that once his weight wouldn’t allow him to sit in—much less fly.

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“I was over the weight limit for two people for this plane,” said Thompson from a hangar in Addison. He credits bariatric surgery 20 years ago for helping him get his life off the ground—but, he still had questions.

“Every diet that’s out there—every surgical option that’s out there—only treats the symptom,” said Thompson. “It does not treat the cause. Why do we eat, is where the real mystery is, why do we eat that way.”

Now, researchers at UT Southwestern are working to unravel that mystery—saying they can prove that the brain functioning of obese patients is in fact different.

“We were pretty stunned,” said Nancy Puzziferri, MD. Dr. Puzziferri is an assistant professor of surgery at UT Southwestern, and the senior author of the study. “At the same time, it explained so much of the behavior we would hear about from patients.”

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Using MRI technology, researchers studied the brain activity of obese patients and lean study subjects while they were fasting. Brain activity was measured again after they had eaten and reported that they were full.

“In people who don’t have a weight problem, those areas of the brain completely die down. There’s no discernible activity,” found Dr. Puzziferri. “And in people who have a significant weight problem, it’s as if they haven’t eaten at all: their brains were acting just as they were when they were hungry.” According to Dr. Puzziferri, the findings provide “validation” for those whose struggles with weight are often misunderstood. “It’s objective, scientific evidence that they’re different from people who don’t have a weight problem.”

Following bariatric surgery, researchers found that the brain activity of obese patients began to more closely resemble that of lean patients. They say the long term goal is to find a way to mimic those hormonal changes that drive the brain activity—without the risks associated with surgery. New research is treatment is also critical, researchers say, because over time those hormonal changes often begin to revert and the patient’s pre-surgery appetite can return.

“I do not know a single obese person who likes being obese,” said Thompson, who is thrilled that the medical community is moving beyond what he calls the ‘math’ of weight loss. “It provides a window of hope,” said Thompson, “because we all just think that we’re doing it because we’re defective. We’re broken. Why is this happening? That’s where the real hope can start coming in.”

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