Metabolism describes the chemical reactions involved in maintaining the living state of the cells and the organism. In our laboratory, we are interested in the metabolic pathways that result in liver disease when ill-functioning and also the biosynthetic pathway of the heme group. To that end, we use a combination of cellular, biochemical and biophysical techniques and, most specially, NMR spectroscopy. For instance, we have recently developed a methodology to describe the metabolism in a nutshell by using 31P-NMR spectroscopy.