Investigative Study on Sensory Perception of Food in Anorexia and Bulimia Nervosa: A Proposed Experimental Design Using Quasi-Experimental, Cross-Sectional Approach to Examine Food Preference Shifts or Intensified Enjoyment of Food in Eating Disorders
Eating disorders, such as anorexia nervosa (AN) and bulimia nervosa (BN), are complex conditions that significantly impact food intake and binge-eating episodes. A recent study aims to shed light on the relationship between taste perception, food preferences, and eating disorders (EDs).
1. Taste Perception Alterations in EDs
Research suggests that patients with AN may exhibit reduced somatosensory-gustatory responsiveness, particularly in brain regions like the inferior parietal lobe (IPL). This decreased activation may lead AN patients to rate food stimuli as less pleasant than healthy controls, potentially facilitating fasting and restrictive eating behavior.
While the literature on taste thresholds across weight ranges is inconsistent, no clear consensus has been drawn about alterations specifically linked to EDs like AN or BN.
2. Impact on Food Preferences and Eating Behavior
Diminished taste sensitivity or altered neural response to food may contribute to decreased appetite or selective food avoidance seen in restrictive EDs (AN). In contrast, for EDs involving binge eating (e.g., BN, BED), disruptions in sensory and cognitive control might be linked to episodes of binge eating, where taste preferences could shift toward highly palatable, often sweet or fatty foods.
3. Influence on Food Intake and Binge Episodes
In AN, decreased gustatory pleasure and somatosensory responses likely suppress appetite and food intake, reinforcing restrictive behaviors. For individuals with EDs involving binge eating, physiological factors such as delayed gastric fullness, nausea, or digestive distress, often compounded by psychological distress and impaired hunger/fullness cues, influence binge-eating episodes.
Summary Table
| Factor | Anorexia Nervosa (AN) | Bulimia Nervosa (BN) / Binge Eating Disorder (BED) | |----------------------------------|--------------------------------------|-------------------------------------------------------| | Taste Perception | Decreased gustatory response, food rated as less pleasant[2] | Less clearly defined; potential shifts toward palatable foods| | Food Preferences | Food avoidance/restriction, selectivity[3] | Possible preference for high-calorie foods during binges | | Neural Activation | Reduced IPL/somatosensory-gustatory activation[2] | Not well defined in sources provided | | Impact on Food Intake | Suppressed appetite and intake, facilitates fasting[2] | Episodes of binge eating influenced by gut-brain distress[4] | | Physical/GI Symptoms | Constipation, slow gastric motility, distress during recovery[4] | Gastrointestinal distress, nausea, possible purging[4] |
This study, which has been approved by the Swiss ethics committee (CER-VD, n° 2016-02150) and the Ethics Review Panel of the University of Luxembourg, will present four mixtures of sweet-fat stimuli to patients with AN and BN, as well as healthy individuals, using a sensory two-alternative forced-choice test. The study aims to investigate whether aversions to the taste of high-calorie food are related to the suppression of energy intake in restricting-type AN, and whether an increased hedonic valence of sweet, caloric-dense foods may be part of the mechanisms triggering binge-eating episodes in BN.
The expected results on cognitive mechanisms in the top-down processes of food hedonics will complement current models and contribute to the refinement of interventions aimed at changing cognitive aspects of taste aversions, establishing functional food preferences, and managing food cravings associated with binge-eating episodes. The role of cognitions influencing these mechanisms will also be examined.
If taste response profiles are differentially linked to ED types, future studies may investigate whether taste responsiveness could be a useful diagnostic measure in the prevention, assessment, and treatment of eating disorders (EDs).
1. Potential Use of Taste Perception in ED Diagnosis
If systematic differences in taste response profiles are found between various eating disorders (EDs), such as anorexia nervosa (AN) and bulimia nervosa (BN), it may lead to the exploration of taste responsiveness as a possible diagnostic tool in the prevention, assessment, and treatment of EDs.
2. Understanding the Science of Lifestyle and Mental Health
The study of cognitive mechanisms in the top-down processes of food hedonics could provide valuable insight into the complex relationship between food preferences, mental health, and lifestyle choices, potentially leading to the development of more effective interventions for managing eating disorders (EDs) and food cravings.
3. Expanding Knowledge on Health-and-Wellness and Food-and-Drink
The investigation into the relationship between taste perception and eating disorders (EDs) not only contributes to the understanding of the underlying mechanisms of EDs but also provides important information about the impact of food and drink on overall health-and-wellness, mental-health, and lifestyle. This knowledge can be beneficial in promoting healthier food-and-drink choices and reducing the prevalence of EDs.
