Label-free, noninvasive, rapid and cost-efficient: combining Raman spectroscopy with high-throughput flow cytometry reveals the metabolic performance of individual cells of a population in their natural context. Cellular metabolism supports pivotal processes: from microbial carbon and nitrogen cycling, to crop production for food and energy homeostasis, to cancer progression. Although powerful, traditional bulk metabolomic approaches obscure the heterogeneity inherent in cell populations, masking rare but functionally significant subpopulations. Single-cell sorting technologies have emerged to analyze this complexity and isolate cells with sp...