A new UCLA Health review reveals that America’s obesity epidemic is fueled not just by diet and exercise, but by stress, discrimination, and social hardship—factors that disproportionately impact low-income and minority communities.
Published in Clinical Gastroenterology and Hepatology, the study highlights how social determinants of health—such as poverty, limited access to nutritious food, unsafe neighborhoods, and systemic racism—can alter gut bacteria and brain function. These changes disrupt appetite regulation, increase cravings for ultra-processed foods, and impair motivation for physical activity.
“Neighborhood disadvantage is linked to reduced gut microbiome diversity and a higher presence of harmful bacteria,” said Dr. Arpana Church, who led the review. These biological shifts, she explained, promote inflammation and weaken self-control, reinforcing cycles of emotional eating and obesity.
The impact begins early. Environmental stressors and social adversity can shape the brain-gut microbiome from prenatal stages, setting the stage for lifelong obesity risk. In communities of color, chronic exposure to violence, isolation, and racism-related stress compounds the problem.
Church emphasized that reversing obesity trends requires both personalized care and systemic reform. “Healthcare providers must screen for social determinants and tailor treatment plans to reflect biological and psychosocial challenges,” she said.
While policy changes are essential, individuals can take steps to protect their health—prioritizing affordable nutritious foods, building social connections, and engaging in stress-reducing activities.
See: “How Stress and Social Struggles Fuel America’s Obesity Crisis” (September 3, 2025)
