Egg Nutritional Composition
Eggs are an excellent source of high-quality protein. Nutritionists rate eggs as equivalent to the meat foods group. It is stated that eggs contain "complete protein" with all essential amino acids needed for growth and body repair. They are also present at levels higher than most other foods.
The protein in eggs is the most nutritious and readily available form known. It is used as the standard against which all other food proteins are compared. Since all amino acids are present at high levels, eggs are often used to supplement the nutritional value of other foods.
Eggs also contain high levels of vitamins and trace minerals. They are an excellent source for vitamins A, D, and the B-complex. All vitamins required by man are present in eggs except for vitamin C. They also contain many trace minerals including iron, copper, iodine and zinc.
The yolk contains essentially all the fat within the egg. Almost two-thirds of the egg fat is in unsaturated forms that are liquid and readily digestible. Lecithin and other fat components make the egg a valuable ingredient in many recipes. These substances contribute to improved stability of salad dressings and baked items.
When considering all nutrients present in eggs, it is often assumed that eggs are high in energy. However, each large egg contains only 80 calories. They are ideal for diets of persons who must control their weight by eating nutritious, light-energy foods.
Eggs have often been maligned because of their cholesterol content. However, cholesterol is an essential component of our bodies and is required for the synthesis of vitamin D and many hormones. Although cholesterol is essential for health, it is not an essential nutrient in the human diet. The body can readily manufacture all the cholesterol it requires.
In the past, some scientists have suggested that a reduction of dietary cholesterol will help protect against heart disease; other scientists with equal authority disagree. Recent research indicates that moderating dietary energy intake, controlling of body weight within the recommended range, and having a physically active lifestyle may be more important for reducing heart disease than reducing dietary cholesterol intake. Additional medical research will clarify the relationship between dietary nutrients and heart disease. Until more information is available, it is advisable that persons with elevated blood cholesterol levels consult with and follow the advice of their physicians.
Source: Mississippi State University Extension Service: http://www.msstate.edu/dept/poultry/4heggs.htm