The egg’s yolk helps support eye health because it is a source of:
• Lutein and zeaxanthin: which help reduce the risk of macular degeneration (AMD)
• Omega-3 fatty acids: studies suggest essential fatty acids may help protect against AMD and dry eye
• Vitamin E: an antioxidant that may slow the progression of AMD and cataract formation
Generally speaking, the darker orange the yolk, the more nutrients it contains. Darker yolks come from healthy pastured hens that have a varied diet; not only corn and grain but also the occasional bug and vegetable. Note: Organic does not mean pastured!
Most eggs found in supermarkets come from factory farms. One of the downsides of factory farmed eggs is that the caged hens are fed only grain resulting in a lighter yellow yolk. While not exactly harmful per se, these lighter yellow yolks are less effective at delivering the nutrients you expect from eating an egg.