Numerous nutritional research projects are in progress. However, the majority of evidence to date appears to show the efficacy of these chemicals to slow or inhibit the progression of macular degeneration. Medical research has shown that the macular region of the retina is composed primarily of cone cells containing high levels of the carotenoids Zeaxanthin and Lutein. The chemical structures of both Lutein and Zeaxanthin are such that they readily absorb blue light waves, but allow the free passage of yellow light waves. Blue light is the shorter wave length and more energetic radiation in the visible range of the electromagnetic spectrum.
Yellow light is a longer wave length and less energetic form of visible light.
It is the yellow waves which pass on through our eyes, while the blue waves are scattered. The importance here lies in the fact that the structural components of cells on the retina can be readily damaged by the highly energetic blue light waves. Because of their strong absorption of these damaging high energy blue light radiations, Lutein and Zeaxanthin help to protect the delicate cellular structures of the retina. Lutein can not be made by the human body, and zeaxanthin can only be made from Lutein in our bodies. Therefore, the Lutein that we require for good vision must be obtained from the diet.