Nature Communications reported that short-term restriction of animal products rapidly alters human proteogenomic profiles at the molecular level. The study by A. Simistiras, O. Bocher, C. Emmanouil and colleagues examined how limiting animal-derived foods influences both gene activity and proteomic signals. For translational research and clinical nutrition design, the result suggests that observational diet studies may be confounded by fast-acting biological shifts. It also provides a framework for using proteogenomics as a near-term readout in diet-intervention trials.