Elevated body mass index (BMI) is associated with increased multi-morbidity and mortality. The investigation of the relationship between BMI and brain organization has the potential to provide new insights relevant to clinical and policy strategies for weight control. Here, we quantified the effect of BMI on the functional connectivity of the Default-Mode (DMN), Central Executive (CEN), Sensorimotor (SMN) and Visual (VN) networks in 496 healthy individuals that were studied as part of the Human Connectome Project. We found that elevated BMI was associated with disrupted functional integration of sensory-guided (SMN, VN) with internally controlled (DMN, CEN) networks, implicating increased attention to sensory stimuli as a possible mechanism underpinning overeating and weight gain. Our results suggest that weight control strategies should expand to include wider societal policies that incorporate modifications to eating environments and to the visual presentation and branding of food products.