Incorporation of stable isotope labelled precursors enables estimation of the kinetics of lipid synthesis and turnover (dynamic lipidomics) in the clinical as well the experimental setting. Recent advances in tandem mass spectrometry extend the analytical possibilities from measurements of isotope enrichments to determinations of intact substrates. Incorporations of deuteriated choline, ethanolamine and inositol can be determined by precursor and neutral loss scans of phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol, respectively. This experimental approach provides information on the kinetics of individual phospholipid molecular species and has considerable potential to probe diseases of lipid metabolism in vivo.