Overeating may change the brain by altering a key feeding suppression system, a study has indicated.
Eating too much can erode the mind’s natural controls on food intake, leading to neurological alterations which fuel obesity and pathological overconsumption, according to research on mice.
The findings, published in the journal Science, show that diet affects the lateral hypothalamic area (LHA), a brain region associated with regulating food intake.
It found neurons in obese mice on a high-fat diet were altered in a way that disrupted the body’s feeding suppression system, encouraging overeating.
Encoding properties of individual LHA glutamatergic neurons were tracked through obesity, showing “greatly attenuated reward responses”, the paper says.
The study suggested “similar alterations within LHA neurons may contribute to human obesity”.
The study was carried out by an international group of researchers led by the University of North Carolina at Chapel Hill.
It says: “Until now, obesity’s effects on the LHA have been unclear.
“We hypothesise that the excitatory LHAVglut2 signal represents the activation of a brake on feeding to suppress further food intake.
“Here, we demonstrate that LHAVglut2 neurons are sensitive to satiety state: when motivation for food is low, they are more excitable than when motivation is high.
“Chronic HFD (high fat diet) modification within LHAVglut2 cells ultimately hinders their neuronal activity, thereby weakening an endogenous attenuator of feeding to promote overeating and obesity.”
Obesity is a growing health concern which affects more than 500 million people worldwide and around one in four adults in the UK.