Eggs existed long before chickens, according to On Food and Cooking: The Science and Lore of the Kitchen by Harold McGee. These all-in-one reproductive cells, incorporating the nutrients to support life, evolved about a billion years ago. The first eggs were hatched in the ocean. As animal life emerged from the water about 250 million years ago, they began producing an egg with a tough leathery skin to prevent dehydration of its contents on dry land. The chicken evolved only about 5,000 years ago from an Asian bird.

Eggs are an excellent nutrient-dense food that packs six grams of protein, a bit of vitamin B-12, vitamin E, riboflavin, folic acid, calcium, zinc, iron, and essential fatty acids into a mere 75 calories. Second to the lactalbumin protein in human milk, eggs have the highest quality protein of any food. In addition to being good for the body, eggs can be prepared in a variety of tasty ways.
Want more nutritious eggs in your diet? Find out what the hen was fed. In fact, research has proven that better chicken feed results in better eggs. Free-range hens allowed to forage on barnyard plant food produce eggs that are lower in cholesterol than commercially-fed caged hens. Studies comparing eggs from the average hen-laying factory with those of free-range chickens fed diets high in essential fatty acids showed the chicken on a healthier diet produced eggs higher in the heart-healthy omega-3 fatty acids.

Studies are under way to produce what are dubbed "designer eggs," eggs in which the fatty acid profile of the egg yolk has been modified by altering the hen's diet. In an interesting experiment, giving hens feed rich in flax seed and fish oil (with their omega 3 fatty acids) increased the amount of omega 3 fatty acids in their eggs, producing "omega eggs." So, even when it comes to chickens, "you are what you eat." Egg consumers are not used to asking their market managers how the hens were fed that laid their eggs. Yet, if enough consumers start asking the question egg buyers would start putting feed information on the labels. The egg of the future will only be as healthy as the consumer demands.