How an empty stomach can sabotage weight loss
Posted Jun 18, 2014
Everyone’s heard the phrase “Don’t drink on an empty stomach.” While this is certainly true when it comes to alcohol consumption, a growing body of research looking at the connections between nutrition and neuroscience suggests that this admonition might be revised to say, “Don’t eat on an empty stomach!” Now, obviously, a growling stomach is a sign that you should, in fact, eat. The message here is that you want to try to avoid reaching the point of complete starvation as this can lead to unhealthy decisions regarding food.
A recent study showed that participants found high calorie foods, such as chocolate, more appealing after an overnight fast compared to when they had recently eaten, while the appeal of low calorie foods did not change regardless of condition (1). Moreover, using functional magnetic resonance imaging (fMRI), this study also found increased activation of the orbitofrontal cortex — a brain region involved in decision making (2) and food reward evaluation (3) — when participants who had undergone an overnight fast viewed images of high calorie foods. This effect was less pronounced when viewing low calorie foods, providing additional evidence that going too long without food can predispose you to choosing high calorie items in particular.
When trying to understand our biological responses to hunger, sometimes it’s helpful to time travel back and think about the food landscape in more primitive times when food was markedly less abundant and could require great effort to obtain. If a person during this time was very hungry and operating out of a calorie deficit, it would have been extremely adaptive to consume high-energy foods, especially to hold them over until the next time food was available. Fortunately, for most people living in industrialized societies today, however, food scarcity does not threaten our survival.
Instead, many of us (69 percent of American adults were considered either overweight or obese in 2012) are attempting different diet and exercise strategies to keep us from the effects of high calorie foods! In this context, going for an extended period without food isn’t adaptive; in fact, it only sets us up to fail. This is why it is so important not to skip breakfast and helpful to keep a healthy snack, like an apple or a handful of almonds, with you throughout the day. Grabbing a light bite before heading out to a dinner party might also help to safeguard against our natural inclination towards high calorie foods when we’re famished.
1. Goldstone AP, Prechtl CG, Scholtz S, Miras AD, Chhina N, Durighel G, Deliran SS, Beckmann C, Ghatei MA, Ashby DR, Waldman AD, Gaylinn BD, Thorner MO, Frost GS, Bloom SR, Bell JD (2014). Ghrelin mimics fasting to enhance human hedonic, orbitofrontal cortex, and hippocampal responses to food. American Journal of Clinical Nutrition 99(6): 1319-1330.
2. Bechara A, Damasio H, Damasio AR (2000). Emotion, decision making and the orbitofrontal cortex. Cerebral Cortex 10(3): 295-307.
3. Kringelbach ML, O'Doherty J, Rolls ET, Andrews C (2003). Activation of the human orbitofrontal cortex to a liquid food stimulus is correlated with its subjective pleasantness. Cerebral Cortex 13(10): 1064-71.
Dr. Nicole Avena is a research neuroscientist/psychologist and expert in the fields of nutrition, diet and addiction. She has published over 50 scholarly journal articles, as well as several book chapters on topics related to food, addiction, obesity and eating disorders. She recently edited the book, Animal Models of Eating Disorders (Springer/Humana Press, 2013), and she has a book Why Diets Fail (Ten Speed/Crown) that was released January 1, 2014. Her research achievements have been honored by awards from several groups including the New York Academy of Sciences, the American Psychological Association, the National Institute on Drug Abuse, and her research has been funded by the National Institutes of Health (NIH) and National Eating Disorders Association. She has appeared on several television programs, including Good Day NY and The Couch.