A study from Florida International University quietly shifts what we thought we knew about the origins of obesity: in children as young as four, the brain already bears the imprint of body weight, with measurable differences appearing in regions that govern hunger, reward, and desire. Using advanced MRI imaging on 159 preschool-aged children, researchers found that BMI—alone among body-size measures—correlated with structural variations in these foundational circuits. The discovery does not yet tell us which comes first, the body or the brain, but it asks us to reconsider how early in life the