Dr Veronica Witte | Central mechanisms of obesity and obesity-associated brain damage

Obesity, “the” epidemic of the 21st century, has been linked with abnormal functionality of homeostasis brain networks and changes in higher-order cognitive functions, yet the underlying mechanisms remain unclear. Recently, we showed in the large neuroimaging cohort of the Health Study of the Leipzig Research Center for Civilization Diseases (LIFE) that individuals with lower cortical thickness in orbitofrontal areas exhibited higher symptom scores of “food addiction”, which mediated a higher body mass index (BMI). On the long run, being obese might provoke brain damage: In older adults of the LIFE-study we found that higher BMI and more so visceral fat is linked to subtle alterations such as lower functional connectivity and directed diffusivity, as well as more overt changes such as less grey matter volume and more lesions in the white matter, even after controlling for confounders. Differences in BMI-associated areas further correlated with differences in processing speed and memory performance, linking a higher BMI, mediated through structural changes, to worse cognition. Upcoming longitudinal studies are now needed to confirm these hypotheses and to identify factors that help to prevent or reverse the development of obesity and obesity-associated brain damage.