Obesity Predisposition Traced To The Brain’s Reward System

I’ve previously expressed concern about erosion of the boundary integrity of the disease model undermining acceptance of addiction as an illness. Buy, if there’s science to support it, no problem.

A new study suggests that obesity is linked to dopamine production:

“Baseline dopamine levels were 50 percent lower and stimulated dopamine release was significantly attenuated in the brain reward systems of obesity-prone rats, compared with obesity-resistant rats. Defects in brain dopamine synthesis and release were evident in rats immediately after birth,” said Emmanuel Pothos, PhD, assistant professor in the department of pharmacology and experimental therapeutics at TUSM and member of the neuroscience program faculty of the Sackler School of Graduate Biomedical Sciences.

“Previous research has demonstrated that food intake leads to an increase in the release of dopamine, in the circuits that mediate the pleasurable aspects of eating,” Pothos explains. “Also, chronic food deprivation resulting in decreased body weight leads to decreased dopamine levels. Therefore, increased food intake may represent a compensatory attempt to restore baseline dopamine levels.”

Pothos says, “These findings have important implications in our understanding of the obesity epidemic. The notion that decreased dopamine signaling leads to increased feeding is compatible with the finding from human studies that obese individuals have reduced central dopamine receptors.” He speculates that an attenuated dopamine signal may interfere with satiation, leading to overeating.

What I don’t get is how these two statements go together:

Defects in brain dopamine synthesis and release were evident in rats immediately after birth

and

These findings have important implications in our understanding of the obesity epidemic.

Is there a new epidemic of babies being born with dopamine regulation problems at birth? We frequently attribute increases in obesity as a product of lifestyle changes. Is this suggesting that it’s related to changes in brain function that are identifiable at birth?