Offloading computation to cloud has been widely used for extending battery life of mobile devices. However, little effort has been invested in applying the offloading techniques to communication-related tasks. We propose Smart Diet, a toolkit to identify the constraints that reduce offloading opportunities and to calculate the energy-saving potential of offloading communication-related tasks. Smart Diet traces the method-level application execution and estimates the allocation of communication energy cost from traffic traces. We discuss key features of Smart Diet and show some preliminary results using a prototype implementation.