Neurobiology of eating disorders - an overview

The Neural Correlates of Body Image Processing in Anorexia Nervosa and Bulimia Nervosa: An Activation Likelihood Estimation Meta-Analysis of fMRI Studies

Body image concerns are key prognostic and pathogenic factors of anorexia nervosa (AN) and bulimia nervosa (BN). This study aimed to investigate the neural mechanisms underlying body image perception across its two domains of estimation and satisfaction in anorexia and bulimia patients and healthy controls (HC). Systematic searches were conducted across eight databases, including PubMed; Cochrane Library; Ovid; Google Scholar; Sage Journals; Scopus; PsycInfo; and ScienceDirect, from database inception until the 23rd of April 2023. The sample pertained to 14 functional magnetic resonance imaging (fMRI) studies and 556 participants, with tasks primarily including image and silhouette-based body estimation and satisfaction paradigms. ALE meta-analysis was conducted to investigate significant clusters of activation foci across the different studies. Shared activations were observed between HC, AN, and BN patients in cortical regions related to object manipulation and recognition, visuospatial awareness, and memory and negative affect regulation. Differential activation in interoceptive and higher-order cognitive or affective control regions likely hold the key to pathological body distortion. This study outlined commonalities and differences in the correlates driving healthy body mapping and eating disorder pathology. Our findings provide pertinent implications for future research, current clinical interventions, and therapeutic outcomes.

Interactions between emotions and eating behaviors: Main issues, neuroimaging contributions, and innovative preventive or corrective strategies

Emotional eating is commonly defined as the tendency to (over)eat in response to emotion. Insofar as it involves the (over)consumption of high-calorie palatable foods, emotional eating is a maladaptive behavior that can lead to eating disorders, and ultimately to metabolic disorders and obesity. Emotional eating is associated with eating disorder subtypes and with abnormalities in emotion processing at a behavioral level. However, not enough is known about the neural pathways involved in both emotion processing and food intake. In this review, we provide an overview of recent neuroimaging studies, highlighting the brain correlates between emotions and eating behavior that may be involved in emotional eating. Interaction between neural and neuro-endocrine pathways (HPA axis) may be involved. In addition to behavioral interventions, there is a need for a holistic approach encompassing both neural and physiological levels to prevent emotional eating. Based on recent imaging, this review indicates that more attention should be paid to prefrontal areas, the insular and orbitofrontal cortices, and reward pathways, in addition to regions that play a major role in both the cognitive control of emotions and eating behavior. Identifying these brain regions could allow for neuromodulation interventions, including neurofeedback training, which deserves further investigation.

Eating Disorders and Suicidal Behaviors in Adolescents with Major Depression: Insights from the US Hospitals

Objective: To evaluate the odds of association between suicidal ideation and/or attempt with comorbid eating disorders in adolescents with major depressive disorder (MDD). Methods: We conducted a cross-sectional study and included 122,020 adolescents with a primary diagnosis of MDD from the nationwide inpatient sample (NIS, 2012–2014). They were sub-grouped by a comorbid diagnosis of eating disorders (N = 1675). We calculated the adjusted odds ratio (aOR) using a logistic regression model with demographic confounders for associations of eating disorders with suicidal ideation and attempt. Results: Suicidal ideations were seen in a higher proportion of adolescents with eating disorders (46.3% vs. 14.2% in those without eating disorders). On the contrary, a low proportion of adolescents with eating disorders had suicidal attempts (0.9% vs. 39.4% in those without eating disorders). Overall, eating disorders were associated with higher odds for suicidal ideations (aOR 5.36, 95% CI 4.82–5.97) compared to those without eating disorders, but with lower odds of suicidal attempt (aOR 0.02, 95% CI 0.01–0.03). Conclusions: Adolescents with MDD and comorbid eating disorders had five-times increased odds of suicidal ideations but lower odds of a suicide attempt. Self-harm/injurious behaviors are early signs of suicidal ideations in these patients. A collaborative care model is required for the screening, early diagnosis, and management of adolescents with eating disorders to improve their quality of life.

Comparison of plasma nucleotide metabolites and amino acids pattern in patients with binge eating disorder and obesity

Binge eating disorder (BED) increasingly affects population, but the mechanisms of the disease and its biomarkers are not well characterized. Recently, plasma purines, pyrimidines, amino acid and nicotinamide metabolites profiling attracted attention in studies on pathology and biomarkers of mental disorders but has not been adequately studied in BED. Blood and plasma samples were taken from patients with adult obese with BED (n = 20) and control adult obese without BED (n = 17). Plasma samples were analyzed for nucleotides and amino acid concentrations with high-performance liquid chromatography-mass spectrometry. BED had a significantly (p < 0.05) lower uridine and hypoxanthine to creatinine ratio compared to the control group. Among the amino acids BED patients had significantly (p < 0.05) lower concentrations of glutamic acid, leucine, isoleucine and the whole branched-chain amino acids group, while the concentration of citrulline was increased. Among nicotinamide metabolites, 1-methylnicotinamide levels were significantly (p < 0.05) lower. This study highlights potential use of profiling nucleotide metabolite and amino acid pattern in BED patients that may provide information on mechanisms and potential biomarkers. However, further investigation in larger population is necessary to identify clinical correlates of the observed changes.

Stigma: the representation of anorexia nervosa in UK newspaper Twitter feeds

BACKGROUND

There is evidence that the representation of mental health in newspapers has an influence on readers' attitudes, however, relatively little is known about how the industry presents accounts of anorexia nervosa. Further, the industry increasingly uses Twitter as a medium for reaching readers and this remains an under-examined area of research.

AIMS

To explore the representation of anorexia nervosa in the UK national press' Twitter feeds.

METHOD

Frame analysis was used to examine the manner in which anorexia nervosa was represented in the Twitter feeds of all national UK newspapers between 2009 and 2019 (n = 332). This qualitative approach used Braun and Clarke's stages of thematic analysis, while drawing on Van Gorp's use of a frame matrix to support the definition of the news frames.

RESULTS

The analysis identified four news frames: social model, illness model, stress-recovery model and clickbait model.

CONCLUSIONS

The newspapers drew on a range of perspectives in their representation of anorexia nervosa, which typically were not stigmatising in their accounts. However, there was a pattern of using sensationalistic images in some of the tweets, which may encourage readers to view people with anorexia nervosa as Other, and as a consequence contribute to stigmatisation.

Perspective: Public Health Nutrition Policies Should Focus on Healthy Eating, Not on Calorie Counting, Even to Decrease Obesity

Calorie-focused policies, such as calorie menu labeling, seem to result in minor shifts toward healthier choices and public health improvement. This paper discusses the (lack of) relations between energy intake and healthy eating and the rationale for shifting the focus of public health nutrition policies to healthier foods and meals. We argue that the benefits of reducing caloric intake from low-quality foods might not result from the calorie reduction but rather from the reduced consumption of low-quality foods. It is better to consume a given number of calories from high-quality foods than a smaller number of calories from low-quality foods. It is not possible to choose a healthy diet solely based on the caloric value of foods because calories are not equal; they differ in nutritional quality according to their source. Foods are more than just a collection of calories and nutrients, and nutrients interact differently when presented as foods. Different subtypes of a macronutrient, although they have the same caloric value, are metabolized and influence health in different ways. For instance, industrial trans fats increase lipogenesis and the risk of heart diseases, whereas monounsaturated fats have the opposite effect. Food processing and cooking methods also influence the nutritional value of foods. Thus, public health nutrition policies should stop encouraging people to focus mainly on calorie counting to fight noncommunicable diseases. Instead, policies should focus on ingredients, dietary sources, and food processing and cooking methods.