< Back to previous page

Project

The psychobiological impact of semi-starvation on food choices in anorexia nervosa.

Already during World War II, the famous Minnesota Starvation Experiment in healthy men showed that semi-starvation causes disturbed food desire, elevated negative affect, stress and disordered eating choices. We see this also in anorexia nervosa (AN) patients, where cognitive-affective processes are severely impacted by underlying physical processes once patients reach a semi-starvation state. Recent rodent research, together with limited data in healthy humans, now suggests that the diet-sensitive microbial ecosystem in the gut (gut microbiota) drives food choices via microbiota-gut-brain signaling. Specifically, the production of short-chain fatty acids (SCFA) from dietary fiber in the gut by its microbiota are hypothesized to play a key role in this mechanism, steering energy balance, stress responses and appetite, as well as motivation and affect. This leads to the following, new question: Might changes in SCFA production in the gut by semi-starvation also influence AN patients’ disturbance in positive and negative affect, self-control, energy expenditure, stress and subsequent aberrant food choices? If so, we would, for the first time, have an underlying biological explanation for the reported cognitive-affective effects of semi-starvation. If this biological hypothesis rings through, new breakthrough therapies would appear on the horizon of the treatment of AN. Unfortunately, however, clinical human research in AN on this topic is so far virtually nonexistent. Our group aims to fill this gap, by investigating the relationship between the gut microbiota and blood SCFA with two psychobiological endophenotypes involved in aberrant eating habits in AN: Positive Valence System (positive affect, drive to eat and taste, resulting in affect-related food choices) and the Arousal/Regulatory Systems (eg. energy balance and stress arousal). In several published and ongoing studies of the Mind-Body Research (MBR) lab (E. Vrieze), we validated the importance of both endophenotypes in different psychiatric illnesses, including eating disorders. We would now like to take this research to a next level by synergistically pairing it up with the world-leading TARGID team (L. Van Oudenhove, K. Verbeke)’s research in human microbiota-gut-brain interactions. Together we could propose and corroborate the first biological explanation for the debilitating feedback loop caused by semi-starvation in already very sick patients. To test causality, we want to conduct a triple-blind, placebo-controlled randomized clinical trial, to investigate the effect of SCFA administration on affect-related food choices under stress and re-nourishment in AN. With this project, we aim to not only better understand the underlying causality of perpetuating aberrant nutritional choices in anorexia nervosa, but, as there is currently no empirically derived agreement on therapeutic re-nourishment, our findings may also help shape more theoretically based guidelines for refeeding methods in this difficult to treat illness.

Date:14 Sep 2021 →  Today
Keywords:anorexia nervosa, gut-brain communication, human microbiota
Disciplines:Biological psychiatry, Behavioural sciences
Project type:PhD project