Brain Differences Linked to Teen Weight
Written by Sameeha Salman
Edited by Hannah Parducho
Jan 18, 2021
Edited by Hannah Parducho
Jan 18, 2021
We often attribute weight gain to making unhealthy food choices and a lack of physical activity.
This is partially true, but the reason why people chose to eat excessive amounts of junk food and to refrain from exercising remained largely unknown. Today, researchers find that there are differences in a particular region of the brain that cause some people to be more predisposed to obesity than others.
Researchers have discovered that there is a region in the brain that is linked to how we process the role of food in our lives. This region is called the Nucleus Accumbens, or the NAcc. The NAcc becomes active and triggers a dopaminergic response, which is the feel-good response we experience when we engage in rewarding behaviors. In adults, it has been found that inflammation of the NAcc, observed via MRI brain imaging, is associated with an unhealthy diet consisting of fatty foods. For those with NAcc inflammation, the brain processes the satisfaction and good taste of unhealthy food as a signal to eat more of it. Consequently, an inflamed NAcc may influence weight gain.
Researchers are now interested to see if NAcc inflammation can be used to predict weight gain in adolescents. They took MRIs of kids’ brains at the beginning of their study and at the one-year follow-up. Increased density, or inflammation, of the NAcc was found to be associated with an increased waist circumference and BMI. They also found that increased saturated fat in the diet is associated with a more inflamed NAcc. As a result, the dopaminergic response associated with eating high-calorie foods is enhanced. An increased intake of high-calorie, fatty food links back to the inflammation of the NAcc region of the brain that makes one experience increased satisfaction when consuming unhealthy foods.
This study is in its early stages, and the kids will continue to be tracked throughout their child and teen years. This will give us more information about the relationship between brain structures and adolescent obesity. For now, we are able to see that there may be a relationship between brain structures and pediatric obesity: the food choices we make may encourage us to eat more of that food and may contribute to the growth of the NAcc. It is commonly known that the factors that promote obesity include a lack of physical activity, unhealthy food habits, genetics. This new discovery also suggests the size of certain brain structures in adolescents is important in predicting one’s predisposition to obesity. Choosing to eat healthy foods and exercise regularly are more behavioral aspects to obesity that can be controlled, but the size of our brain regions cannot. While obesity may be mediated by factors that seem out of our control, that should never stop us from trying to lead a healthy, balanced life.
Works Cited
Rapuano, Kristina M., et al. “Nucleus Accumbens Cytoarchitecture Predicts Weight Gain in Children.” PNAS, National Academy of Sciences, 27 Oct. 2020, www.pnas.org/content /117/43/26977.