Extra-large Egg Whites & Nutrition

Extra-large egg whites are a rich source of animal protein that provides a wide range of vitamins and minerals. Nutrients in extra-large egg whites include potassium, selenium, pantothenic acid, magnesium, niacin and sodium. Egg whites are also low in fat, cholesterol and calories. One extra-large egg white contains approximately 17 calories. Egg whites may be substituted for whole eggs in recipes if you are trying to watch your total fat and calorie intake.

Significance of Protein

According to the U.S. Department of Agriculture, about 20 percent of your total calorie intake should come from protein sources. In "The Food Bible," author Judith Wills says proteins are constantly being broken down into smaller units called amino acids. Wills states that amino acids from protein are significant because they play a role in the composition of your hair, nails, skin, blood, enzymes and hormones. The proteins you eat are considered "complete" if they contain all the essential amino acids your body needs. Animal proteins such as egg whites are considered complete or high-quality proteins.

Expert Insight on Cholesterol

The American Heart Association recommends that you eat less than 300 mg of cholesterol each day. One egg contains about 210 mg of dietary cholesterol. High cholesterol levels increase your risk of heart disease, atherosclerosis, heart attack and stroke. Other factors such as high blood pressure, diabetes, age, gender and family health history increase your risk even more for coronary heart disease. Your cholesterol intake is a factor you can control. Dietary cholesterol is primarily found in the yolk of the eggs. Substituting whole eggs with egg whites significantly cuts back the amount of cholesterol in your diet.

Function of Niacin

Many of the beneficial nutrients are found in the egg yolk, according to Cholesterol-and-Health.com. However, an extra-large egg white contains more than 80 percent of a B-complex vitamin called niacin. Niacin functions by metabolizing and utilizing carbohydrates, fats and proteins as energy. According to "The Nutrition Bible," niacin helps ensure the health of your skin, digestive tract and nerves.

Function of Magnesium

Egg whites are good sources of the mineral magnesium. An extra-large egg white contributes about 4 g of the mineral. Your bones, teeth, muscles and soft tissues are composed of magnesium, according to "The Food Bible." In addition, magnesium activates enzymes that play a role in the metabolism of carbohydrates, proteins and fats.

Considerations for Sodium

The American Heart Association recommends eating less than 1,500 mg of sodium per day. A high sodium intake is linked to high blood pressure and heart disease. One extra-large egg white contains only about 50 to 55 mg of sodium. Sodium is a mineral that works in conjunction with potassium to regulate fluid balances in your body. According to "The Nutrition Bible," it also plays a role in stimulating nerve impulses and metabolizing proteins and carbohydrates.