 The study will use 3H-cholesterol bound to albumin particulate cholesterol to assess the ability of HDL to transport cholesterol to the liver to be eliminated. This process is called Reverse Cholesterol transport and is one of the main mechanisms by which HDL protect against atherosclerotic cardiovascular disease. The availability of a method to assess RCT is important for the development of new drugs which affect RCT and may result in useful treatments for atherosclerosis. 