“It's probably not going to be all that effective to just give people advice to eat less and exercise more,” said study lead author Kevin Hall, a senior investigator at the National Institutes of Health. “You might want to start to focus on a similar sort of way that people want to change any sort of habit that they have, and this is suggesting that certain eating behaviors that are keeping people obese may have a neurobiological underpinning related to their habits.”
Developing an effective weight loss plan for obese patients may require examining the environmental factors that contribute to a compulsion to overeat, and replacing those behaviors.
A recent study by the Robert Wood Johnson Foundation and Trust for America's Health found little gains have been made over the past decade toward reducing the country's obesity rate. While the rate has appeared to have stabilized after nearly 30 years of increase, it continued to rise in many states, with Mississippi and West Virginia going above 35% in 2013.
“Thinking about advice that physicians give to their patients in a little bit of a different way might help,” Hall said.
The study examined 43 men and women with varying amounts of body fat. In addition to having an effect on the habit-forming part of the brain, researchers found that obese people had less dopamine activity in the region that controls reward, making food less rewarding.
Hall said the study could not find a causal link between obesity and dopamine activity, adding that it was not clear at this point whether obesity was a cause or an effect of differing brain chemistry. He said future research would look at dopamine activity and eating behavior over time as people engage in healthier activities, such as increased physical exercise and eating less.
Follow Steven Ross Johnson on Twitter: @MHsjohnson