In Vivo Real-Time Metabolic Isotopic Tracing via Breath Analysis upon Deuterated Water Ingestion: A Proof-of-Concept Study

Z. Yin, K. D. Singh, Z. Tang, M. Richard, J. Zeng, U. Frey, P. Sinues, X. Li

Real-Time Metabolic Tracing Through Breath

This proof-of-concept study explores the use of SESI-HRMS for noninvasive, real-time metabolic isotopic tracing through exhaled breath after deuterated water ingestion. By monitoring deuterium incorporation in breath metabolites, the approach enables dynamic tracking of metabolic responses across fasting and postprandial states. The study revealed distinct labeling patterns associated with short-chain fatty acids, energy metabolism, and host-microbial metabolic activity, demonstrating the potential of breath-based SESI-HRMS as a powerful tool for metabolic phenotyping, nutritional studies, and future clinical research.