It is shown that narrow 1H NMR resonances may be observed in cancer cells, and that these belong to fatty acyl chains of membrane lipids. A variety of NMR techniques such as Gaussian-Lorentzian deconvolution, and T1 and T2 measurements, may be used to subdivide these resonances further. The results of these various methods require that in the membrane structures the observed lipids tumble isotropically and sufficiently rapidly to give motionally narrowed 1H NMR lines.