A single large egg yolk contains about 2.7 grams of protein and roughly 55 calories. That’s less total protein than the white of the same egg, but the yolk is actually more protein-dense by weight, and it delivers that protein alongside a rich package of fats, vitamins, and minerals that the white lacks.
Protein in One Large Egg Yolk
A large egg yolk weighs around 17 grams. Of that, 2.7 grams is protein and 4.5 grams is fat, making fat the dominant macronutrient. In calorie terms, about 20% of a yolk’s energy comes from protein while the remaining 74% comes from fat. That’s nearly the opposite ratio of an egg white, which is almost pure protein.
If you eat a whole large egg, the total protein is roughly 6.3 grams. The yolk contributes about 43% of that. So while the white gets most of the credit as the “protein part” of the egg, the yolk carries a meaningful share.
Yolk vs. White: Protein Per Gram
Here’s a detail that surprises most people: egg yolk contains more protein per gram than egg white. Yolk has 16.4 grams of protein per 100 grams, compared to 10.8 grams per 100 grams for the white. The reason the white delivers more total protein per egg is simply volume. There’s about twice as much white as yolk in a standard egg, so the white wins on absolute grams even though it’s less concentrated.
This matters if you’re comparing foods by weight or making recipes that call for yolks only. Two large egg yolks give you about 5.4 grams of protein, which is comparable to an ounce of chicken breast, though with a very different calorie and fat profile.
How the Body Uses Egg Yolk Protein
Protein quality varies widely between foods, and egg yolk protein ranks at the top. When researchers strip the fat from egg yolk protein and score it against human amino acid requirements, it achieves a perfect score of 100, meaning it provides every essential amino acid your body needs in the right proportions. Studies have also found that lipid-free egg yolk protein digests faster than milk casein, a common benchmark for protein absorption.
In practical terms, the protein in egg yolks is highly usable. Your body doesn’t waste much of it, and it delivers a complete amino acid profile without needing to be paired with other protein sources.
Cooking Changes How Much Protein You Absorb
Eating eggs raw, whether blended into a smoothie or mixed into a shake, significantly reduces how much protein your body actually absorbs. Protein digestion from raw eggs is roughly 40% lower than from cooked eggs. A study in healthy young men found that after eating five boiled eggs, blood levels of essential amino acids, leucine, and branched-chain amino acids were all meaningfully higher compared to eating five raw eggs with the same protein content.
The heat from cooking unfolds (denatures) the egg proteins, making it easier for your digestive enzymes to break them apart. This applies to both the yolk and the white. So if you’re eating egg yolks for their protein, cooking them in any form (scrambled, boiled, poached, fried) will help you get more out of each gram.
What Else the Yolk Delivers
People searching for yolk protein are often deciding whether to eat whole eggs or just the whites. The protein difference alone is modest: you lose 2.7 grams by discarding the yolk. But the yolk is where nearly all of an egg’s micronutrients live. It contains the egg’s full supply of fat-soluble vitamins (A, D, E, and K), most of its B vitamins, and all of its choline, a nutrient important for brain function that most people don’t get enough of. The yolk also carries iron, phosphorus, and carotenoid pigments that support eye health.
The tradeoff is caloric. Throwing away the yolk saves you about 55 calories and 4.5 grams of fat per egg. For someone tracking calories tightly while trying to maximize protein intake, whites are more efficient. For general nutrition, keeping the yolk gives you a far more complete food for a relatively small calorie cost. Two whole eggs provide about 12.6 grams of protein, roughly 150 calories, and a broad range of nutrients that are hard to match from any other single food at that calorie level.