The investigators know that metformin works at the level of the cells in the body by acting on a protein called Cyclic amine monophosphate- Response Binding Elements (CREB) binding protein or Constitutive Reverter of eIF2α Phosphorylation (CREP) Binding Protein (CBP). What the investigators do not know is how this process is affected when the dose of the metformin is increased or changed.