Obesity alters brain and hinders weight loss

New research published in Nature Metabolism highlights how obesity can impact the brain, preventing long-lasting weight loss. The study conducted a controlled trial with 60 individuals, 30 of whom were medically obese and 30 who were of non-obese weight. Participants were fed carbohydrates, fats, or water via a nasogastric tube to understand the direct connection between the gut and the brain. Their brains were evaluated through functional MRI and single photon emission computer tomography to understand the brain's response to these foods. Researchers discovered that in lean people, there was slowing in the striatum resulting in the brain understanding that the body was fed, and dopamine levels also increased indicating feeling satisfied. However, in patients with medical obesity, there was no slowing in the striatum, dopamine levels did not rise, and the brain did not recognize the sensation and satisfaction of being full after eating. Those participants who lost 10% of their body weight within three months did not have any change in their brain's ability to recognize fullness or feeling satisfied. This leads to the idea that those who lose weight may quickly regain their weight back as there may be an irreversible change within the brain in medically obese individuals. Obesity is a complex idea that has many ramifications for the brain. As medical experts learn about the biological effects of obesity, they are having more luck and finding long lasting obesity treatments. While this data and information are compelling, there's more to be learned about the brain and obesity. Further research is needed to understand when the brain loses its capacity to regulate food intake and what determines that switch.