Eggs are loaded with a variety of beneficial nutrients.
However, the nutritional value of an egg can vary greatly, depending on whether you eat the whole egg or just the egg whites.
This article takes a detailed look at the nutritional profile of egg whites and explores whether they're a healthier choice than whole eggs.
Egg whites are the clear, thick liquid that surrounds the bright yellow yolk of an egg.
In a fertilized egg, they act as a protective layer to defend a growing chicken from harmful bacteria. They also provide some nutrients for its growth.
Egg whites are made up of around 90% water and 10% protein.
So if you remove the yolk and choose just the egg white, then the nutritional value of your egg changes considerably.
The chart below shows the nutritional differences between the egg white of a large egg and a whole, large egg (1):
|Egg White||Whole Egg|
|Protein||4 grams||6 grams|
|Fat||0 grams||5 grams|
|Cholesterol||0 grams||211 mg|
|Vitamin A||0% of the RDI||8% of the RDI|
|Vitamin B12||0% of the RDI||52% of the RDI|
|Vitamin B2||6% of the RDI||12% of the RDI|
|Vitamin B5||1% of the RDI||35% of the RDI|
|Vitamin D||0% of the RDI||21% of the RDI|
|Folate||0% of the RDI||29% of the RDI|
|Selenium||9% of the RDI||90% of the RDI|
As you can see, an egg white contains fewer calories and micronutrients, as well as less protein and fat, than a whole egg.
SUMMARY An egg white contains fewer calories than a whole egg. It is also lower in protein, cholesterol, fat, vitamins, and minerals.
This protein is high-quality and complete, meaning it contains all nine essential amino acids in the amounts your body needs to function at its best (2).
Given that whole eggs provide you with only slightly more protein for quite a few extra calories, egg whites can be an appealing choice for people who are trying to lose weight.
SUMMARY The egg whites from a large egg provide 4 grams of protein and only 17 calories. This can make them a good food choice for people trying to lose weight.
However, all of the cholesterol and fat in eggs is found in the egg yolk. Egg whites, on the other hand, are almost pure protein and contain no fat or cholesterol.
For years, this meant that eating egg whites was considered healthier than eating whole eggs (8).
Nevertheless, for a small number of people — called "hyper-responders" — eating cholesterol will raise blood levels slightly (11).
Additionally, given that egg whites contain almost no fat, they are significantly lower in calories than whole eggs.
This can make them a good choice for people trying to limit their calorie intake and lose weight.
SUMMARY Egg whites are low in cholesterol and fat. This makes them a good choice for people who need to limit their cholesterol intake, as well as those trying to lose weight.
Egg whites are usually a safe food choice. However, they do carry some risks.
Though egg whites are safe for most people, egg allergies can occur.
An egg allergy is caused by your immune system incorrectly identifying some of the proteins in eggs as harmful (16).
Mild symptoms can include rashes, hives, swelling, a runny nose, and itchy, watery eyes. People can also experience digestive distress, nausea, and vomiting.
While it's rare, eggs can cause a severe allergic reaction known as anaphylactic shock.
This causes a number of symptoms, including a drop in blood pressure and severe swelling in your throat and face — which could be deadly if combined (17).
Salmonella Food Poisoning
Raw egg whites also pose a risk of food poisoning from the bacteria Salmonella.
Salmonella can be present in the egg or on the eggshell, though modern farming and cleanliness practices can minimize this risk.
Furthermore, cooking egg whites until they are solid significantly reduces your risk of this problem (18).
Reduced Biotin Absorption
Raw egg whites may also reduce the absorption of the water-soluble vitamin biotin, which is found in a wide variety of foods.
Biotin plays an important role in energy production (19).
Raw egg whites contain the protein avidin, which can bind to biotin and stop its absorption.
In theory, this could be a problem. However, you would have to eat large amounts of raw egg whites to cause a biotin deficiency.
Additionally, once the eggs are cooked, avidin doesn't have the same effect.
SUMMARY There are some risks associated with eating raw egg whites, including allergic reactions, food poisoning, and biotin deficiency. However, the risk for most people is small.
Egg whites are high in protein yet low in calories, fat, and cholesterol — making them a good weight loss food.
They may also benefit those who have high protein requirements but need to watch their calorie intake, such as athletes or bodybuilders (20).
However, compared to whole eggs, egg whites are low in other nutrients.
Whole eggs contain a wide range of vitamins, minerals, extra protein, and some healthy fats.
What’s more, despite their high cholesterol content, one analysis found no link between egg intake and heart disease risk (21).
In fact, the same review noted that eating up to one egg per day may reduce your risk of having a stroke (21).
Moreover, the nutrients found in eggs have been linked to a host of health benefits.
However, if you’re on a very strict reduced-calorie diet, have a family history of high cholesterol and heart disease, or already have high levels of cholesterol, then egg whites may be a healthier choice.
SUMMARY Egg whites are lower in calories than whole eggs. However, they also lack many of the beneficial nutrients found in egg yolks.
Egg whites are a high-protein, low-calorie food.
Yet for most people, there aren't many benefits to choosing egg whites over whole eggs, as whole eggs provide you with many more beneficial nutrients.
That said, for some people — particularly those who need to limit their cholesterol intake or are trying to lose weight — egg whites can be a healthy food choice.