When addicts talk about their first euphoric experience with their narcotic of choice, very often they describe it as the feeling they spent the duration of their drug-using years attempting to revisit. It turns out, the same phenomenon of “chasing the high” may apply to overweight and obese women’s response to food as well.
A study released online on Sept. 29 in the Journal of Neuroscience found that as women overate and gained weight, they got less pleasure from eating. In brain scans, these women showed less activity in the “reward” pathways of the brain — the neurological corridors that respond to pleasure — after eating. (More on Time.com: Why Americans Are Fat: We Literally See More Food as Less)
University of Texas at Austin psychologist Eric Stice studied 26 overweight and obese volunteers, who were subjected to fMRI brain scans as they sipped both sugary milkshakes and a flavorless liquid. The group was tested twice over 6 months. Those who gained weight over the course of the study showed a corresponding muted pleasure response to the milkshake. Women who lost or maintained weight did not show the same decrease. (More on Time.com: Want Good Health? There Are 10 Apps for That)
Obese people are known to have fewer pleasure receptors in the brain than thin people to start, according to the new study, whose findings suggest that overeating blunts the reward pathway further. New Scientist reports:
The result suggests that overeating may push people onto a slippery slope akin to a drug addict’s craving for ever-larger doses. “People are having to eat more and more to chase the high,” says Stice.
More studies are needed in this area, to sample a larger group of people and to figure out whether the “tolerance” can be reversed by weight loss.
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