Faulty Brain Signaling Results In Overeating From High Fat Diet
Not only are high fat foods bad for you and low in nutritional value. They can hold dangerous food additives that may actually make you want to eat more.
New findings published in Neuroscience Program in Substance Abuse (N-PISA) at Vanderbilt University found that defective signaling resulted in overeating in mice, leading to obesity.
"We have always been struck by how much animals -- and even people -- will over-consume tasty high-fat foods, even though they might be technically feeling full," Dr. Aurelio Galli, one of the authors of the study, said in a statement. "A high fat diet causes people to eat more, which ultimately impairs the ability of obese people to successfully control their caloric intake, lose weight and maintain weight loss. We have conducted several studies trying to understand why a high fat diet has this effect."
In this recent study, researchers zeroed in on one particular insulin signaling pathway in the brain and how it works in specific brain cell circuits. Defects in insulin signaling can override the body's natural homeostatic mechanisms in favor of the reward mechanisms, leading to obesity, according to the findings.
"Our findings reveal a system that is designed to control eating of rewarding foods that are high in fat and possibly sugar," Galli said. "This system can be hijacked by the very foods that it is designed to control. Eating a high-fat or high-carbohydrate diet feels rewarding, but also appears to cause changes in the brain areas that are involved in controlling eating, by causing for example insulin resistance. Our study shows that when specific signaling in these areas of the brain is disrupted, it leads to a vicious cycle of increasing, escalating high-fat diet intake that likely further cements changes in these brain areas."
Statistics show that at least one-third of adults in the United States are considered obese and more than one-third, with an estimated annual medical cost of obesity in the U.S. was $147 billion in 2008 U.S. dollars; the medical costs for people who are obese were $1,429 higher than those of normal weight, according to the Centers for Disease Control and Prevention (CDC).
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