Eggs are a good source of high-quality protein. They provide important sources of iron, vitamins, and phosphorus. As a nutritional source of vitamin D, eggs rank second only to fish liver oils. Eggs are low in calcium, which is discarded in the shell, and contain very little vitamin C.
Eggs provide a unique and well-balanced source of nutrients for persons of all ages. Hard-cooked egg yolks are of the great nutritional value as a major supplementary source of iron for infants. When children reach one year of age they may also be given egg whites. Eggs contain significant nutritional value, which is essential during rapid body growth and therefore is an excellent food for young children and teenagers.
Low caloric value, ease of digestibility, and high nutrient content make eggs valuable in many therapeutic diets for adults. For older people, whose caloric needs are lower, eggs are an easy, inexpensive, and nutritious food to prepare and eat. Availability, modest cost, ease of preparation, popular taste appeal, and low caloric value give eggs a primary advantage for human nutritional needs.