We reproduced Western-style, fast-food consumption by treating diabetes-prone, C57Bl/6J mice with a combination diet consisting of solid high fat and liquid sucrose (HFHSD) or fructose (HFHFrD) and monitored in vivo β-cell insulin sensitivity noninvasively with reporter islets in the ACE expressing a β-cell–specific, insulin-resistance biosensor (13). The gene discussed is INS; the disease is diabetes mellitus.