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After returning home from a hard day’s work, many amongst us are accustomed to putting our feet up and relaxing with an alcoholic beverage. Some amongst us regularly hit the pub after office hours to down a few drinks, and if it is a Friday, some go on a pub-hopping spree till the wee hours. But if the findings from a recent research study are to be believed, too many alcoholic drinks invite obesity.
According to the scientists of this study, women are more sensitive to the appetite-inducing effects of alcohol, but men should not rest easy either.
Alcohol’s effect on the brain leads to overeating tendencies
That glass of red or white wine tastes heavenly and you are fondly attached to it. But it not only goes to your gut but also does curious things to your brain and makes it crave more food than you would have ideally liked to consume.
Recently, an experiment was carried out on several women at healthy weights. On one occasion, the participants were intravenously administered alcohol that went to their brains directly bypassing the digestive system. On another occasion, the subjects were injected with saline water.
It was found that after the alcohol reached their brains, the women ate more food than they normally consume. The women who had been injected with saline water reported no such increase in food intake. The scientists also discovered that after consuming alcohol, the hypothalamus became more sensitive to food aromas than non-food smells. The scientists believe that this activation of the hypothalamus could be the reason why after consuming alcohol, people tend to overeat.
The use of food odors to trigger hunger is deliberate. The hunger-inducing effect of food aroma is believed to be stronger and more visceral than visual images of food. The former is also a conditioned stimulus because it indicates the actual presence of food, so hunger responses to food aromas can provide more clues about the neurological basis of hunger.
According to the findings from another experiment, food aromas trigger reward-related regions of the brain, like the bilateral insula, anterior and posterior cingulate, opercular cortex, and ventral striatum. Incidentally, these areas of the brain are also activated in the presence of drug, and alcohol cues and are known to trigger cravings for addictive substances.
The landmark Eiler study explains a phenomenon that was noted in an earlier study. According to this study, wine affects appetite almost immediately. During the study, the subjects were made to drink red wine about 20 minutes before meal. The control group drank wine during the starter and main courses.
It was found that the group that drank wine before the meal consumed more food during the starter course than the control group. At the time of this experiment, scientists were not sure if there is a neurological basis to explain this phenomenon. They now know that the clues to hunger are in the brain, and not solely in the gut.
The fact that the experiment was carried out on women is interesting considering that an earlier study had found out that women are neurologically programmed to have less control over their hunger pangs than men. In this study carried out on men and women who had been fasting, it was discovered that after a period of not eating, men reported less hunger pangs than women. The men showed less activity in certain regions of the brain, like the hippocampus, amygdala, insula, striatum, and orbitofrontal cortex. These regions are known to be involved in conditioning, processing emotions, and motivation.
Overeating is one of the principal causes of obesity. The above-mentioned studies should serve as warnings especially to women. Because they are neurologically predisposed to have less control over hunger pangs, they should try and avoid alcoholic drinks before meal times.
Hunger plays games
The results of the above experiments expose a dangerous tendency in humans — we tend to eat and end up overeating even if we are not hungry or have been deprived of food for prolonged periods. All that we need to gobble up is to have certain areas of our brains stimulated artificially.
These results corroborate the findings of an earlier study, in which the subjects reported an increase in their desire to eat when presented with appetizing food. The sight of the food activated certain areas of the brain, like the anterior insula, superior temporal, and right orbitofrontal cortices. The activation of these areas of the brain triggered hunger pangs and made subjects overeat.
Regular consumers of alcoholic beverages need to be wary of another co-relation that scientists have unearthed. Obese individuals tend to exhibit greater activity in the reward areas of their brains (insula/frontal operculum) in response to anticipation and consumption of appetizing food than leaner people. So a drink or two will not only increase their hunger pangs but also create a vicious cycle of overeating.
It is evident that hunger has neurological roots! It is no wonder that restaurants go to great lengths to make their foods look tempting. And it is evident why alcoholic drinks are served before meals.
Alcohol and obesity
The above-mentioned findings and the peculiar way in which food triggers hunger have led scientists to ponder on the association between alcohol and obesity. Alcoholic drinks have high calorie content, and given that these have been proven to trigger overeating tendencies, it can be safely assumed that having one drink too many can lead to weight gain. These concerns by scientists are valid at times when drinking alcohol is on the rise.
These studies should encourage people to examine their drinking habits. Those who love their sherries and champagnes need not become teetotalers but they can certainly find ways to limit the availability of food just after they have had a drink. Keeping away from finger foods and not sitting down to a lavish five-course meal just after an aperitif are effective ways to stop oneself from overeating.
Alvarez, J. (2015). Alcohol’s BOLD effect on food intake Science Translational Medicine, 7 (295), 295-295 DOI: 10.1126/scitranslmed.aac8109
Bragulat, V., Dzemidzic, M., Bruno, C., Cox, C., Talavage, T., Considine, R., & Kareken, D. (2010). Food-Related Odor Probes of Brain Reward Circuits During Hunger: A Pilot fMRI Study Obesity, 18 (8), 1566-1571 DOI: 10.1038/oby.2010.57
Caton, S., Bate, L., & Hetherington, M. (2007). Acute effects of an alcoholic drink on food intake: Aperitif versus co-ingestion Physiology & Behavior, 90 (2-3), 368-375 DOI: 10.1016/j.physbeh.2006.09.028
Eiler, W., Džemidži?, M., Case, K., Soeurt, C., Armstrong, C., Mattes, R., O’Connor, S., Harezlak, J., Acton, A., Considine, R., & Kareken, D. (2015). The apéritif effect: Alcohol’s effects on the brain’s response to food aromas in women Obesity, 23 (7), 1386-1393 DOI: 10.1002/oby.21109
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