It’s 3 a.m. You've had a few drinks after a night of dancing off the work week blues. And you’ve lost count of how many pizza slices have disappeared into your drooling gob as you lay sprawled, pantsless, on the kitchen floor.
A new study has shed light on why this scene may sound familiar to anyone who’s ever indulged a little too hard on a Friday night.
As it turns out, alcohol may activate some of the brain cells responsible for hunger pangs.
While previous research has shown that people are prone to overeating after drinking alcohol, it wasn’t clear until now what the biological reasons for this phenomenon might be.
The link was especially perplexing considering alcohol’s high-calorie content, “and calorie intake usually suppresses brain appetite signals,” the authors wrote in the study, which was recently published in the journal Nature Communications.
In this new study, the researchers looked at the effect of alcohol consumption on food intake in a group of mice (the findings are likely to apply to people as well since humans have the same types of brain neurons as those examined in the study.)
The mice were injected with alcohol over three days. As a comparison, the researchers injected the mice with saline over the three days before and after the alcohol injections. The mice were given access to the same amounts of food and water throughout the study period.
Surprise, surprise: the rodents ate way more on the days when they were injected with alcohol.
They then looked at the mice’s brains throughout their experiments, and discovered that certain hunger-promoting brain cells known as Agrp neurons were activated after the mice were injected with alcohol. These neurons were not activated when the mice were injected with saline.
The researchers then artificially inhibited those neurons’ activity in the mice, and the mice promptly stopped overeating.
The conclusion? Alcohol may help sustain what the researchers dubbed “false starvation alarms” in the brain. In simpler terms, alcohol might make the mice feel hungry despite getting calories from the alcohol itself.
One thing to note, said neurobiology professor Jessica R. Barson of Drexel University College of Medicine (who was not involved in the study), was that the mice did not voluntarily drink the alcohol, which could skew the results as they translate to humans.
“Nobody injects themselves with alcohol,” Barson told Live Science. “We drink alcohol.”
Barson added that the injection procedure may have exerted stress on the mice, which could have affected the results since “stress can change the brain and behavior in powerful ways.”
Let’s hope not, as there’s some comfort in knowing science (and not a frightening lack of willpower) is responsible for all those post-drinking nacho binges.
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