European Association for the Study of Obesity May 10 2025 A major study finds teens with abdominal obesity have enlarged brain areas linked to learning and emotion, raising concerns that excess weight and inequality may disrupt cognitive development and raise long-term dementia risk. Study: National-level and state-level prevalence of overweight and obesity among children, adolescents, and adults in the USA, 1990–2021, and forecasts up to 2050 . Image Credit: New Africa / Shutterstock New