Does a lack of self-control lead to obesity or does obesity reduce self-control?
That question was at the centre of a new study by Western University which found a reciprocal connection between obesity and reduced self-control.
Researchers looked at the structure and function activity in the prefrontal cortex, an area of the brain involved in decision making. They found the level of activity in that region can not only affect a person's dietary choices, but can also influence it. Those with reduced activity in the prefrontal cortex may be prone to eat more, which can result in changes to the brain that can lead to overeating more in the future.
“It’s not just the case that obesity is causing these issues in the brain structure and function, but it is this reciprocal relationship—that differences in brain structure and function can cause obesity, that’s really important,” Cassandra Lowe, study co-author and member of Western’s BrainsCAN postdoctoral fellowship, said in a statement. “Our review shows that if you have lower prefrontal activity, it can pre-dispose you to overeating, which in turn can lead to weight gain and obesity.”
The findings could be used to identify new ways to treat obesity. Up until now, obesity neuroscience has primarily focused on dysfunctions in the brain's reward pathways.
“By reframing the issue of obesity around prefrontal activity, as opposed to reward region responsivity, we can explore treatments and preventative measures that may inhibit unwanted weight gain," said Lowe.
Exercise, for example, can increase prefrontal cortex activity which can help an individual ignore food cravings, said Lowe, who went onto note more mindful eating can also be an effective way to improve activity in the prefrontal cortex.
“By focusing on the healthiness and long-term consequences of the food we are eating instead of just taste, we are able to make better dietary choices,” added Lowe.
Establishing healthier eating habits during childhood and adolescence can ensure the prefrontal cortex functions correctly, the study found.
“At this age, an adolescent’s prefrontal cortex is not fully developed, which in part explains the impulsive and hot-headed decision making of our youth—the control system isn’t fully engaged yet. Related to this aptitude for poor decision making are poor eating habits, with adolescents eating more unnecessary calories from junk foods than any other age group, a habit that can last into adulthood,” said Amy Reichelt, study co-author and a member of Western’s BrainsCAN postdoctoral fellowships.
The study was published Wednesday in the journal Trends in Cognitive Sciences.