Recently, there has been tremendous scientific interest in the role of phospholipids and particularly phosphatidylcholine (lecithin) in a variety of biological processes. These include the involvement of phosphatidylcholine in biological membranes, as a component of plasma lipoprotein, as a transporter of choline in the body, and also as a "reserve", and possibly only source of unesterified choline. Moreover, numerous clinical studies have recently...