Quick Answer: One large egg white (33 g) contains about 17 calories, 3.6 g of protein, 0.06 g of fat, 0.2 g of carbohydrate, 55 mg of sodium and zero cholesterol.
Four whites come to roughly 68 calories and 14.4 g of protein. Egg white is close to pure protein, and the protein is complete. But the framing that makes egg whites the “healthy” half of the egg does not survive the data: the yolk holds about 43 percent of the egg’s protein and almost all of its micronutrients, including essentially all the choline, vitamin D, B12 and folate. Discarding yolks is a reasonable choice for specific goals, and a poor default.
Egg White Nutrition Facts
From USDA FoodData Central, rounded. One large egg white weighs about 33 g.
| Nutrient | 1 white | 2 whites | 4 whites | Per 100 g |
|---|---|---|---|---|
| Calories | 17 | 34 | 68 | 52 |
| Protein | 3.6 g | 7.2 g | 14.4 g | 10.9 g |
| Total fat | 0.06 g | 0.1 g | 0.2 g | 0.17 g |
| Saturated fat | 0 g | 0 g | 0 g | 0 g |
| Cholesterol | 0 mg | 0 mg | 0 mg | 0 mg |
| Sodium | 55 mg | 110 mg | 220 mg | 166 mg |
| Potassium | 54 mg | 108 mg | 216 mg | 163 mg |
| Total carbohydrate | 0.24 g | 0.5 g | 1 g | 0.73 g |
| Dietary fibre | 0 g | 0 g | 0 g | 0 g |
| Riboflavin (B2) | ~0.15 mg | ~0.29 mg | ~0.58 mg | 0.44 mg |
| Selenium | ~6.6 mcg | ~13 mcg | ~26 mcg | 20 mcg |
| Vitamin A, C, D, iron, calcium | 0 or trace | – | – | 0 or trace |
Two corrections to figures that circulate widely, including in the earlier text on this page.
- Egg whites are not a source of vitamin B12 or folate. Roughly 93 percent of an egg’s B12 and 95 percent of its folate sit in the yolk. The white’s only meaningful micronutrients are riboflavin, at about 11 percent of the Daily Value per white, and selenium at about 12 percent.
- Sodium is the one number worth watching. A four-white omelette carries around 220 mg before you season it. That is not alarming, but egg whites are often eaten in quantity precisely because they are low in calories, and the sodium scales with them.
Protein: How Much, and How Much You Actually Absorb
Egg white protein is complete, containing all nine essential amino acids, and it is one of the reference proteins nutrition science measures others against. At 3.6 g per white for 17 calories, the protein-to-calorie ratio is excellent.
The part almost nobody mentions is that how you prepare them changes how much of that protein you get.
A stable-isotope study published in the Journal of Nutrition measured true ileal digestibility of egg protein and found it was about 51 percent when eaten raw, against about 91 percent when cooked. Heat unfolds the protein structure and exposes the peptide bonds to digestive enzymes. So raw egg whites tipped into a shake deliver roughly half the usable protein of the same whites cooked, which turns the classic gym-lore approach on its head.
Cooking has a second benefit covered further down: it deactivates avidin, the protein in raw white that blocks biotin absorption.
What You Lose When You Bin the Yolk
This is the section the standard egg-white article leaves out, and it is the most useful thing on the page.
A large egg contains about 6.3 g of protein. The white supplies 3.6 g of it. The yolk supplies the other 2.7 g, roughly 43 percent. Gram for gram the yolk is actually the more protein-dense component, at around 16 g per 100 g against the white’s 10.9 g. It only contributes less per egg because there is less of it.
The micronutrient split is more lopsided still.
| Nutrient | Share in the yolk |
|---|---|
| Choline | ~99.7% |
| Zinc | ~98% |
| Iron | ~97% |
| Folate | ~95% |
| Phosphorus | ~95% |
| Pantothenic acid (B5) | ~94% |
| Vitamin B12 | ~93% |
| Vitamins A, D, E and K | 100% |
| Lutein and zeaxanthin | 100% |
| Riboflavin (B2) | ~35% (the white holds ~65%) |
Two of those deserve a sentence each.
- Choline. One large egg supplies roughly 140 mg, about a quarter of the Daily Value, and virtually all of it is in the yolk. The Dietary Guidelines for Americans identify choline as an under-consumed nutrient, and eggs are one of the few concentrated food sources. Throwing the yolk away removes it entirely.
- Vitamin D. Egg yolk is one of the very few foods that naturally contains it. The white contains none.
So a four-white omelette gives you 14.4 g of protein and almost nothing else. Two whole eggs give you 12.6 g of protein plus choline, vitamin D, B12, folate, selenium, lutein and iron, for about 156 calories. Which is better depends entirely on what you are optimising for, and the honest answer is that most people default to whites for a reason that is out of date.
The Cholesterol Question, Updated
The whole egg-white habit rests on advice that has changed.
A large yolk carries around 185 mg of cholesterol, and for decades that was treated as decisive. The position now:
- The Dietary Guidelines for Americans dropped the 300 mg daily cap on dietary cholesterol in 2015, because dietary cholesterol and blood cholesterol turn out to be only weakly related for most people. When you eat more, your liver tends to make less.
- The American Heart Association now says up to one egg a day fits a heart-healthy pattern for healthy adults, and two a day for healthy older adults with normal cholesterol.
- Saturated fat, not dietary cholesterol, is the main dietary driver of LDL. A 2025 clinical trial in the American Journal of Clinical Nutrition compared diets varying in eggs, cholesterol and saturated fat and concluded it was the saturated fat that moved LDL.
- Mayo Clinic notes that what people eat with eggs bacon, sausage, ham and what they are fried in may matter more for heart risk than the eggs themselves.
This is not a green light for everyone. People with diabetes, existing cardiovascular disease or raised LDL are the group where guidance remains more cautious and where advice should be individual. Calling the yolk “unhealthy” as a general statement, though, does not reflect current evidence.
When Egg Whites Genuinely Make Sense
None of the above means egg whites are pointless. There are real cases for them:
- Hitting a high protein target inside a tight calorie budget. This is the strongest case. Whites deliver protein at roughly 4.7 calories per gram of protein, which very few foods beat.
- A clinician has told you to restrict dietary cholesterol. Some people are genuine hyper-responders, and some conditions warrant it. That is a medical decision, not a default.
- Bulking out a whole-egg dish. The practical middle ground most dietitians suggest: one or two whole eggs plus extra whites. You keep the choline, vitamin D and B12 while adding cheap protein.
- Cooking chemistry. Meringue, angel food cake, macarons and clarifying stock all need whites specifically.
Raw Egg Whites, Avidin and Salmonella
- Avidin. Raw egg white contains avidin, a glycoprotein that binds biotin (vitamin B7) tightly and blocks its absorption. Cooking denatures it. Regularly eating large quantities of raw whites is the scenario where biotin deficiency has actually been documented.
- Salmonella. Eggs do not inherently contain Salmonella. A small proportion may be contaminated, on the shell or occasionally inside, which is why raw or lightly cooked eggs carry a risk. Cooking until both white and yolk are firm removes it.
- Who should avoid raw or undercooked egg: pregnant women, infants and young children, older adults, and anyone immunocompromised.
- Pasteurised liquid egg whites sold in cartons have been heat-treated and are the sensible option if you want to use whites without cooking, for example in a shake. Check the carton says pasteurised.
- Keep eggs refrigerated, and discard cracked ones.
Egg Allergy
Worth stating plainly, because it is the one genuine safety issue with egg whites and the old version of this page mentioned it only in passing.
Egg is one of the nine major allergens that must be declared on US food labels. Most egg allergy is directed at proteins in the white rather than the yolk, ovomucoid and ovalbumin in particular, so “just the whites” is the worse choice for anyone with a suspected egg allergy, not the safer one. Reactions range from hives and stomach upset to anaphylaxis, which is a medical emergency. Egg allergy is common in children and many outgrow it, but that should be confirmed by an allergist rather than assumed.
Egg Yolk vs. Egg White: What’s the Difference?
Frequently Asked Questions
About 17 calories in one large egg white of roughly 33 g, with 3.6 g of protein, almost no fat and no cholesterol. Two whites come to 34 calories and 7.2 g of protein; four come to 68 calories and 14.4 g of protein. Per 100 g, egg white is about 52 calories and 10.9 g of protein. Note that four whites is 68 calories, not 80, a figure that circulates widely and does not match the arithmetic.
About 3.6 g per large white. The whole egg contains around 6.3 g, so the white holds roughly 57 percent of it and the yolk the other 43 percent. Gram for gram the yolk is actually more protein-dense, at about 16 g per 100 g against the white’s 10.9 g; it simply makes up less of the egg. Discarding yolks therefore discards a substantial share of the protein, not just the fat.
Not in general. The white is lower in calories and contains no cholesterol, which suits specific goals. The yolk holds roughly 43 percent of the protein and almost all of the micronutrients: about 99.7 percent of the choline, 93 percent of the B12, 95 percent of the folate, 97 percent of the iron, and 100 percent of vitamins A, D, E and K. Calling the yolk unhealthy reflects cholesterol advice that changed in 2015 rather than current evidence.
Barely. About 93 percent of an egg’s vitamin B12 is in the yolk, and the same is true of folate at around 95 percent. The only micronutrients the white supplies in useful amounts are riboflavin, at roughly 11 percent of the Daily Value per white, and selenium at about 12 percent. Claims that egg whites are rich in B12 and folate are incorrect.
They are a poor idea for two reasons. First, protein digestibility is far lower raw: a stable-isotope study measured true ileal digestibility at about 51 percent raw against about 91 percent cooked, so raw whites deliver roughly half the usable protein. Second, raw white contains avidin, which binds biotin and blocks its absorption; cooking deactivates it. There is also a Salmonella risk with raw egg. If you want whites without cooking, use pasteurised liquid egg whites from a carton.
There is no official limit for egg whites specifically, and no known toxicity from eating them cooked. The practical considerations are sodium, at around 55 mg per white, and the fact that a diet built on whites alone misses the nutrients in the yolk. Most dietitians suggest one or two whole eggs plus extra whites rather than whites alone, which keeps the choline, vitamin D and B12. Anyone with egg allergy, kidney disease or a prescribed dietary restriction should follow their clinician.
Possibly, but this is the group where guidance stays cautious and the answer should be individual. The Dietary Guidelines for Americans removed the 300 mg daily cholesterol cap in 2015 because dietary and blood cholesterol are only weakly related for most people, and the American Heart Association accepts up to one egg a day for healthy adults. People with raised LDL, diabetes or existing cardiovascular disease are a different case. Discuss it with your doctor or dietitian rather than following a general rule.
No, and this is worth knowing because the assumption runs the other way. Most egg allergy is directed at proteins in the white, particularly ovomucoid and ovalbumin, rather than the yolk. Egg is one of the nine major allergens that must be declared on US labels. Reactions range from hives and stomach upset to anaphylaxis, which is a medical emergency. Anyone with a suspected egg allergy needs assessment by an allergist rather than a swap to whites.
About 55 mg per large white, which is 166 mg per 100 g. A four-white omelette therefore starts at roughly 220 mg of sodium before any seasoning, close to 10 percent of the 2,300 mg daily limit. It is not a large amount in isolation, but egg whites are often eaten in quantity because they are low in calories, and the sodium scales up with the portion.
Related Reading
- How many calories are in 2 boiled eggs?
- How to read nutrition labels to make smarter food choices
- Balancing protein, carbs and fats
- Whole milk nutrition facts and how it compares
Sources
- USDA FoodData Central, for egg white and egg yolk nutrient values.
- US FDA, Daily Value on the Nutrition and Supplement Facts Labels.
- Evenepoel et al., Digestibility of Cooked and Raw Egg Protein in Humans, Journal of Nutrition, 1998, measuring true ileal digestibility at about 51 percent raw versus 91 percent cooked.
- Harvard T.H. Chan School of Public Health, The Nutrition Source: Eggs, on dietary cholesterol and the 2015 guideline change.
- Harvard Health Publishing, Enjoy eggs, just skip the bacon, summarising the 2025 American Journal of Clinical Nutrition trial on eggs, cholesterol and saturated fat.
- Mayo Clinic, Eggs: Are they good or bad for my cholesterol?
- American Heart Association, Are eggs good for you or not?
Last reviewed and rewritten September 2026. Nutrient values are from USDA FoodData Central and rounded; egg size varies, so figures scale with the egg. This article is general information, not medical or dietetic advice. If you have an egg allergy, raised LDL cholesterol, diabetes, cardiovascular disease or kidney disease, or you are pregnant, follow the guidance of your doctor or registered dietitian rather than a general rule. Suspected anaphylaxis is a medical emergency. How we research and check this content is described in our editorial process and sources cited policy.
