Jurgen Popp, Thomas Mayerhofer, and colleagues at Leibniz IPHT and Friedrich Schiller University Jena introduce the Personalized Optical Digital Twin (PODT), a Photonics21 contribution to Europe's Virtual Human Twin ecosystem that connects molecular photonics—Raman blood analysis, coherent Raman tissue imaging, and multimodal endomicroscopy—with longitudinal physiology and clinical data. Drawing on the published multicenter INTELLIGENCE trials, the authors argue that technical feasibility and clinical utility must be evaluated separately as the field moves toward Europe's FP10 research agenda.