This dataset contains public data from a preregistered study on metabolic health and effort-based decision-making, centered on whether type-2 diabetes and diabetes risk are associated with blunted motivational tendency. It includes behavioral measures from effort-related economic decision tasks, computational model-derived estimates of motivation, and participant group information spanning people with type-2 diabetes, matched non-diabetic controls, a larger sample with varying diabetes risk, and diabetic patients treated with semaglutide. The dataset is intended for investigating how insulin resistance and metabolic ill-health may shift behavior toward energy conservation and contribute to links between metabolic disease, motivation, and mental health symptoms.