People who are in need of obesity treatment may overeat because they do not experience as much pleasure from eating, new research suggests.
Researchers at the University of Oregon's Lewis Centre for Neuroimaging found that people who displayed little brain activation in response to receiving a milkshake tended to have put on weight a year later.
They also found that those with a particular variation of a gene - TaqA1 - were more likely to have gained weight over time.
Eric Stice, lead author and senior researcher at the Oregon Research Institute in Eugene, commented: "Although recent findings suggested that obese individuals may experience less pleasure when eating, and therefore eat more to compensate, this is the first prospective evidence for this relationship."
He added that the relationship is "even stronger" for people with a certain genetic make-up.
The findings are published in the journal Science and suggest that the popular belief that obese people overeat because they are too fond of food may in fact be far from the truth.
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