In this study we compared diethylation using acetaldehyde-13C2/13C1 and acetaldehyde-2H4/1H4. Light and heavy labeled samples were combined in a ratio of 1:1 and analyzed on a LC-MSMS system using an OrbitrapXL. We analyzed ten techical replicates of each labeling version (13C/12C and 2H/1H) and compared them in regards of labeling yield, quantification accuracy and precision.