A new Cell study from the Shalek and Yilmaz labs suggests liver cells exposed to too much fat—via high fat diet—revert to an immature state that is more susceptible to cancer-causing mutations. Partly supported by the MIT Stem Cell Initiative, the researchers showed that chronic metabolic stress causes individual liver cells to prioritize their own survival over activities important for the tissue and organ as a whole; they also uncovered specific molecular mechanisms by which this occurs.