In what could be the first study of how the brain arbitrates eating when alcohol is involved, scientists concluded that it enhances food aromas for women, leading us to eat more.
Also known as the "aperitif effect," it kicks it into gear even when the alcohol is administered intravenously, according to the research team, whose study was published in the journal Obesity.
"The brain, absent contributions from the gut, can play a vital role in regulating food intake," says Dr. Eiler of the Indiana University School of Medicine.
"Our study found that alcohol exposure can both increase the brain's sensitivity to external food cues, like aromas, and result in greater food consumption."
Working with 35 non-vegetarian, non-smoking women, all of which were at a healthy weight, the research team administered alcohol intravenously as a way to bypass the digestive system.
On another visit, the women were administered saline, as a placebo.
In both situations, their brain responses to the aromas wafting from food versus non-food items were measured via blood oxygenation level dependent (BOLD) response using functional magnetic resonance imaging fMRI technology.
After being teased with the aromas, participants were given a choice of pasta with Italian meat sauce or beef with noodles for lunch.
Those administered intravenous alcohol ate more food than their counterparts who received saline.
Yet one third of the women ate less after receiving the alcohol than the control group ate.
Observation of the scans revealed that after receiving the alcohol, a region of the brain called the hypothalamus became more active in the presence of food odors than when faced with non-food odours.
The scientists take this to mean that sensitivity to food intake is regulated by the hypothalamus in the presence of alcohol, implying that the aperitif phenomenon stems from that part of the brain.
"Today, nearly two-thirds of adults in the U.S. consume alcohol, with wine consumption rising, which reinforces the need to better understand how alcohol can contribute to overeating," says Dr. Martin Binks, Secretary Treasurer and Associate Professor of Nutrition Sciences at Texas Tech University.
