A new era for olfaction - How the COVID-19 pandemic catalyzed research in sensory science and its applications: A review

• Olfaction as a health biomarker. • Pandemic a catalyst for sensory science. • Tech and VR revolutionize research. • Odors profoundly impact human behavior. This review provides a critical synthesis of recent literature on the sense of smell (olfaction, 2020–2025), focusing on its emergent role as a predictive biomarker and its reframing through technology. The widespread impact of the COVID-19 pandemic served as a catalyst, underscoring olfaction's link to systemic health. The synthesis reveals that the sense of smell is a crucial early warning system for chronic conditions; longitudinal studies demonstrate that olfactory decline significantly predicts the onset of neurodegenerative disorders and all-cause mortality, positioning olfactory assessment as a priority for clinical diagnostics. Furthermore, the review highlights two parallel methodological shifts: the integration of olfaction into virtual reality to create immersive experiences and the use of advanced computational models (e.g., language models) to overcome the long-standing challenge of linguistic underrepresentation. These technologies are enabling the digitization and standardization of olfactory research. In the realm of behavior, findings suggest a dual mechanism drives responses, where social chemosignals act as subconscious modulators while effects on mood and eating are often mediated by conscious, subjective perception. A key critical insight is the disconnect between olfactory-driven appetite and subsequent consumption. Future research must prioritize long-term cohort studies and the translation of objective olfactory tests into public health strategies. In conclusion, this paper underscores the dynamic nature of olfactory science and its profound implications for improving clinical risk stratification, safety, and quality of life.