The nutritional value of egg whites lies largely in their high protein count. Other nutrients contained in egg whites include magnesium, potassium, sodium, and choline. Egg whites, unlike the egg yolk, are low in fat, calories, and cholesterol.
Eggs are rich in protein, and the majority of that protein is found in the egg white. With about 3.6 grams of protein, an egg white has about 7% of the recommended daily amount. Protein is used to build and repair tissues, required for strong and healthy hair and nails, and needed for bone health.
Sodium is another major component of the nutritional value of egg whites. The white of the egg contains 55 milligrams of sodium, significantly more than the egg yolk, which contains only about 8 milligrams. Too much sodium in the diet can cause high blood pressure and lead to a greater risk of heart disease and stroke. The recommended daily amount of sodium is 1,500 milligrams, and amounts greater than this may put one at risk.
Another mineral found in egg whites is potassium. Egg whites contain 54 milligrams of potassium, which is essential to human life and is involved in heart function, muscle contraction, and digestion. Adults should consume about 2,000 milligrams of potassium per day.
Although only present in a small amount, magnesium is also part of the nutritional value of egg whites. It is essential for bone formation, nerve and muscle health, and many essential chemical reactions in the body. Egg whites contain 4 milligrams of magnesium. The daily intake of magnesium should not exceed 350 milligrams.
Choline is also included in the nutritional value of egg whites, usually in amounts of under 1 milligram. On the other hand, an egg yolk contains about 116 milligrams of choline, which is an essential nutrient that is involved in cell signaling, the structural integrity of cell membranes, and fat transport and metabolism. It is also required for the functioning of the brain and liver. The daily recommended amount of choline is 425 to 550 milligrams daily.
People on a strict diet tend to avoid eggs because they can be high in cholesterol and fat. Yet the majority of the fat and cholesterol in the egg are contained in the yolk. If one is trying to eat a healthier diet, replacing whole eggs with egg whites can help to cut down on fat and cholesterol, although cutting out the yolk will mean that some of the nutrients of the whole egg are lost.