Although lipid dehydration has been studied at least the last 30 years, a complete dataset of S CH changes upon dehydration has been reported only for DMPC (1,2-dimyristoyl-PC), a saturated lipid whose melting point is slightly below room temperature. As myristic acid is the shortest-chain fatty acid present (in more than 1% ) in the human lecithin composition, DMPC is the most short-chained, and the only saturated, low-melting-point lecithin in the human lipidome. A more standard lecithin for biological studies is POPC (1-palmitoyl-2-oleoyl-PC), which resembles the human plasma membrane in its fluidity and is among the most prevalent membrane lipids in animal cells. To date, the effect of lowering water content on the POPC glycerol backbone and tail segments has not been reported experimentally-a gap we fill in the present study with 1 H-13 C ssNMR experiments that reveal all the S CH in POPC.