Neuroanatomical correlates of food addiction and obesity in the general population

The food addiction model suggests neurobiological similarities between substance-related and addictive disorders and obesity. While structural brain differences have been consistently reported in these conditions, little is known about the neuroanatomical correlates of food addiction. We therefore assessed whether food addiction, assessed with the Yale Food Addiction Scale (YFAS), related to obesity, personality and brain structure in a large population-based sample (n=625; 20-59 years old, 45% women). A higher YFAS symptom score correlated with obesity and disinhibited eating. In a whole-brain analysis, YFAS symptom score was not associated with cortical thickness nor subcortical gray matter volumes. Higher body mass index (BMI) correlated with reduced thickness of (pre)frontal, temporal and occipital cortex. Bayes factor analysis suggested that BMI and - to a smaller extent - YFAS symptom score contributed independently to right lateral orbitofrontal cortex thickness. Our study shows that food addiction is not associated with neuroanatomical differences in a large population-based sample, and does not account for the major part of obesity-associated gray matter alterations. Yet, food addiction might explain additional variance in orbitofrontal cortex, a hub area of the reward network. Longitudinal studies implementing both anatomical and functional MRI could further disentangle the neural mechanisms of addictive eating behaviors. We would like to thank all participants and staff of the LIFE-Adult study, as well as Anja Dietrich for helpful discussions. This work was supported by grants of the European Union, the European Regional Development Fund, the Free State of Saxony within the framework of the excellence initiative, the LIFE–Leipzig Research Center for Civilization Diseases, University of Leipzig [project numbers: 713-241202, 14505/2470, 14575/2470] and by grants of the German Research Foundation, contract grant number CRC 1052 “Obesity mechanisms” Project A1, A. Villringer/M. Stumvoll, SCHR 774/5-1, M. L. Schroeter, and WI 3342/3-1, A.V. Witte, and by a Branco Weiss Fellowship, Society in Science to J. Sacher, and by a NARSAD Young Investigator Award by the Brain & Behavior Research Foundation to J. Sacher, and by the Max Planck Society.