Birgit Olsson Lecture 2014

About Professor Cynthia Bulik

Cynthia Bulik, is Distinguished Professor of Eating Disorders and Director of UNC Center of Excellence for Eating Disorders, University of North Carolina, Chapel Hill. She is also appointed to a half-time position at the Karolinska Institute over a ten-year period. Professor Bulik is a world expert in the eating disorder field and she has an impressive scientific production. Her research on eating disorders (EDs) covers a variety of areas including treatment, animal models, epidemiology, and twin and genetic studies of EDs and obesity. She has written several books, the most recent launched last year, dealing with ”Midlife eating disorders”. 

Summary

"Toward a Science of Eating Disorders: Replacing Myths with Realities"

The title of this year’s lecture was ”Toward a Science of Eating Disorders: Replacing Myths with Realities”. Professor Bulik initiated her lecture by stating that we have to get people to unlearn several myths such as ”dysfunctional families cause anorexia nervosa”. The truth is that no treatment in anorexia nervosa (AN) is highly effective. She then switched to talk about the ”tipping points” of EDs, i.e. what factors trigger ED onset. Cynthia Bulik mentioned among other things genetics, neurobiology, hormones, reinforcers, timing, infection/illness, stressors, microbiome and food availability (in binge-eating disorder). She also encouraged the audience ”to get off our eating disorder island” and get new ideas from other sciences and vice versa, invite scientists from other areas to take interest in ED research. One of the major topics of Cynthia Bulik’s talk was genetics. We know that EDs run in families. Based on Swedish twin studies Cynthia Bulik has shown that the heritability for AN is around 0.60. The genetic studies in AN have moved from candidate genes, where samples in the hundred are needed, to genome wide association studies (GWAS), where samples in thousands are required. By using GWAS single nucleotid polymorphisms (SNPs) can be identified. Experiences from the field of schizophrenia research, where GWAS have been performed in 34000 cases, indicate that in order to identify enough SNPs in AN we need to analyse 25000 cases. Professor Bulik is the lead Principal Investigator of the Anorexia Nervosa Genetic Initative, ANGI, where samples from AN cases in Sweden, Denmark, United States, and Australia are collected. Microbiome was Cynthia Bulik’s next topic. She has the last few years taken interest in the microbiomes of the gut. Her studies have shown that individuals with AN have fewer types of bacteria in the intestine compared to healthy comparison cases. In individuals with AN the bacteria Methanobrevibacter smithii are overrepresented. These bacteria are able to extract more nutrients from the food than bacteria usually are. The presence of these bacteria could possibly explain why a person with AN can survive in spite of a daily calorie intake of 400 kcal. It seems as if these bacteria actually keep the patient alive. Microbiomes could possibly be useful in treatment of bloating and other gastrointestinal symptoms during refeeding. Professor Bulik also pinpointed some neuroscientific aspects of ED research. She explained a neuroinvasive technique, ”optogenetic targeting”, where circuits in the brain can be stimulated by light. She showed an experiment where a circuit in a rodent was stimulated causing craving for fat food. Cynthia Builk concluded the lecture by stating some realities including that AN is a serious biologically influenced psychiatric illness, both genetic and environmental factors influence EDs, families can be our best allies in treatment, and treatment remains inadequate. After the lecture there were questions from the floor.