Although it is not Wai to eat the egg white, concentrated fats are taxing on the digestive system, especially the gall bladder, which must secrete bile salts to emulsify them before being passed on to the jejunum. The white balance the equation better for digestion. Egg white is actually an emulsifier which serves to take the burden off the gall bladder. From:
http://chestofbooks.com/food/science/Ex ... ormed.html
There is an accompanying photomicrograph (Fig.26) on the referenced link which shows the emulsion that has been formed.Fig. 26 shows an emulsion of corn oil and egg white. When the oil is added gradually to the egg white, a foam as well as an emulsion is formed. The large white spheres are air bubbles. The oil is colored red and in the photomicrograph shows black. The illustration also shows that the oil is adsorbed in the film or layer at the interface between a liquid and a gas.