New Delhi– As global obesity rates continue to climb, new research suggests that being overweight may not only affect physical health but also lead to anxiety and impaired brain function, potentially through disruptions in the gut-brain connection.
The study, conducted in mice, found that diet-induced obesity was associated with anxiety-like behavior, altered brain signaling, and significant changes in gut microbiota—factors that may collectively contribute to cognitive decline.
“Our findings suggest that obesity can trigger anxiety-like behaviors, likely due to changes in both brain activity and gut health,” said Desiree Wanders, Associate Professor and Chair of Nutrition at Georgia State University, U.S.
While obesity is already known to raise the risk of conditions like type 2 diabetes and cardiovascular disease, this study shifts focus to its neurological and psychological effects. Researchers used a mouse model that mimics many obesity-related health problems seen in humans.
The experiment involved feeding 32 mice different diets over a period of 21 weeks—16 were placed on a low-fat diet and 16 on a high-fat diet. As expected, the high-fat diet group gained significantly more weight and body fat.
Behavioral tests revealed that the obese mice displayed more anxiety-like symptoms, such as freezing—a common defensive behavior in mice when faced with a perceived threat. These mice also exhibited altered neural signaling in the hypothalamus, a part of the brain responsible for regulating metabolism, which may be linked to cognitive dysfunction.
Further analysis showed clear differences in the composition of gut bacteria between the obese and lean mice, reinforcing the theory that gut microbiota may play a key role in the relationship between diet and brain health.
“These results have serious implications for both public health policy and personal well-being,” Wanders noted. “By deepening our understanding of how obesity affects mental health—especially anxiety—we can better inform strategies for prevention and early intervention, particularly among children and adolescents.”
The study will be presented at NUTRITION 2025, the flagship annual meeting of the American Society for Nutrition, currently underway in Orlando, Florida. (Source: IANS)
