Slow growth of cortex could play role in developing eating disorders as adult finds study

New Delhi, Jan 13 (PTI) Slow maturing of the brain's cortex -- that helps with self-control and decision-making -- during teenage could be a reason for developing eating disorders as a young adult, according to a new research.
     Disordered eating behaviours can be 'restrictive' -- involving dieting and purging in which one deliberately limits food intake to control body weight and shape -- or 'emotional' in response to negative emotions or urges such as binge-eating.
     For the study, published in the journal Nature Mental Health, the researchers led by those at King's College London analysed MRI brain scans of almost 1,000 teenagers from England, Ireland, France and Germany, taken at ages 14 and 23 years. Genetic data and responses to questionnaires assessing the participants' well-being and eating behaviours were also analysed.
     'Brain maturation' in which the cortex or the outer layer of brain decreases in volume and thickness during teenage, was found to be delayed and less pronounced in unhealthy eaters. The cortex is known to help perform higher-level functions such as decision-making and regulating emotions.
     "Age-related decreases in volumes and thickness in several brain regions, particularly in the cerebellum and prefrontal cortex, were less pronounced in restrictive eaters and emotional/uncontrolled eaters, compared with healthy eaters, suggesting protracted (delayed) brain maturation," the authors wrote.
     They said that a delayed maturing of the cortex contributed towards the link between having mental health problems at age 14 and developing unhealthy eating behaviours at age 23, and this connection was unrelated to body mass index.
     In particular, they found that a reduced maturation of the cerebellum -- a brain region that controls appetite -- helped explain the link between one's genetic risk for high body mass index and restrictive eating behaviours at age 23.
     The researchers grouped the participants under three types of eating behaviours -- healthy eaters (42 per cent), restrictive eaters (33 per cent) and emotional or uncontrolled eaters (25 per cent).
     Young people with unhealthy eating behaviours at age 23 were found to have had higher levels of internalising and externalising problems at age 14, compared to healthy eaters. Internalising problems could involve anxiety or depression, whereas externalising ones could involve hyperactivity, inattention or conduct issues.
     Internalising problems significantly increased with age between 14 to 23 among the unhealthy eaters, the researchers said.
     They added that although externalising problems decreased with age across the groups, overall levels were higher among those having emotional or uncontrolled eating behaviours.
     Restrictive eaters were found to have dieted more throughout adolescence compared to healthy eaters.
     On the other hand, some of the emotional eaters showed an increase in dieting between ages 14 and 16, while others showed an increase in binge eating between ages 14 to 19, compared to healthy eaters, the team found.

(This story has not been edited by THE WEEK and is auto-generated from PTI)