The nutritional value of a hard-boiled egg makes it one of natures near perfect foods. It is a significant source of high quality protein and contains a large amount of vitamins, minerals, and amino acids, as well as carbohydrates and fats. The egg has its drawbacks, but it can be an important part of a healthy diet when consumed in moderate amounts.
There are several vitamins in hard-boiled eggs that are vital to good health. They are a good source of vitamins A, B2, B5, and B12. Eggs are also one of just a few foods in which vitamin D naturally occurs. The minerals in hard-boiled eggs include phosphorus, calcium, iron, copper, iodine, and selenium.
One of the most important nutrients in hard-boiled eggs is the protein it contains. The near perfect egg protein is the standard against which all others are measured. It is also very high in amino acids and the omega-3 fatty acid.
Most of the nutritional value of a hard-boiled egg exists in the yolk. Nearly all of the protein, however, comes from the egg white. The white also contains some niacin and riboflavin.
Although nutritional benefits of eggs are many, they do have one major shortcoming: extremely high cholesterol. In fact, just one hard-boiled egg contains about two-thirds of the recommended daily intake. All of the cholesterol is in the egg yolk, so those who have elevated cholesterol levels should limit their consumption of this part of the egg.
Another disadvantage is that eggs have a high fat content. Over 60% of the calories in eggs comes from fat, and one-third of them are from saturated fat. Again, the yolk is the culprit, containing most or all of the fat. The whites are virtually fat free, although they also have little flavor.
There are not many calories in hard-boiled eggs: one large egg contains around 76 calories, most of them in the yolk. The low calorie content and high nutritional value make eggs a good addition to a healthy low calorie diet, although most people should limit their consumption to a few per week.
To obtain the full nutritional benefit of hard-boiled eggs, care should be taken to avoid overcooking them. When they are boiled for too long, the proteins become coagulated and too much hydrogen sulfide is generated. They should actually be cooked at just below a boil to prevent a rubbery consistency.