A single large egg packs 6.3 grams of protein, 5.3 grams of fat, and virtually no carbohydrates (about half a gram) into roughly 72 calories. But the real story is what comes along with those macronutrients: a dense concentration of vitamins, minerals, and other compounds that few single foods can match.
Protein That Sets the Standard
Egg protein is one of the highest-quality proteins you can eat. It has a protein digestibility score of 1.0, the maximum possible rating, meaning your body can absorb and use nearly all of it. This score puts eggs on the same level as whey protein and above most plant-based sources. One large egg delivers about 6.3 grams split between the white and the yolk, with the white containing slightly less protein per gram than the yolk (about 11% protein by weight versus 16% in the yolk). Many people toss yolks to cut calories, but they’re discarding almost half the protein along with most of the vitamins and minerals.
Fat and Cholesterol
The 5.3 grams of total fat in a large egg include 1.6 grams of saturated fat, with the rest being a mix of monounsaturated and polyunsaturated fats. All of this fat lives in the yolk. Standard eggs contain a small amount of omega-3 fatty acids, though the levels are modest. Omega-3 enriched eggs, produced by feeding hens flaxseed or fish oil, can contain roughly 10 to 12 times more omega-3s than conventional eggs.
A single large egg contains about 186 milligrams of cholesterol. The current Dietary Guidelines for Americans recommend keeping dietary cholesterol “as low as possible without compromising nutritional adequacy,” but they no longer set a specific daily cap. For most healthy people, the cholesterol in eggs has a relatively small effect on blood cholesterol levels compared to saturated fat intake. The guidelines include eggs as part of a healthy dietary pattern, grouping them with lean meats and poultry at about 26 ounce-equivalents per week.
Vitamins Concentrated in the Yolk
Nearly all of an egg’s vitamins sit in the yolk. The standout is choline, a nutrient most people don’t get enough of. A single yolk provides roughly 115 to 150 milligrams of choline, and the adequate daily intake for adults is 425 to 550 milligrams. Choline is a building block for a brain chemical called acetylcholine, which plays a direct role in memory and learning. It also supports liver function and helps transport fats out of the liver.
Eggs supply meaningful amounts of several B vitamins, particularly B12 and riboflavin (B2), both of which help convert food into energy. You also get vitamin A (about 245 IU per yolk, contributing to vision and immune function) and a small but useful amount of vitamin D (about 18 IU per yolk). Vitamin D is hard to find in food, so even this modest contribution adds up if you eat eggs regularly.
Minerals Worth Noting
Eggs are a good source of selenium, a mineral that supports thyroid function and acts as an antioxidant. A single egg provides around 5 micrograms of selenium, with the daily recommended intake being 55 micrograms for adults. They also contain phosphorus (important for bone health), zinc (which supports immune function and wound healing), and iodine, another mineral critical for thyroid health. Per 100 grams, eggs contain roughly 198 milligrams of phosphorus, 1.3 milligrams of zinc, and 21 micrograms of iodine.
Iron is present in the yolk as well, though in smaller amounts than you’d get from red meat. The form of iron in eggs is less easily absorbed than the type found in animal muscle, so eggs aren’t a primary iron source, but they contribute to overall intake.
Lutein and Zeaxanthin for Eye Health
Egg yolks get their yellow color from two antioxidants called lutein and zeaxanthin, both of which accumulate in the retina and help protect against age-related damage to your eyes. Spinach and kale contain higher total amounts of these compounds, but the fat in egg yolks makes them significantly more bioavailable. Your body absorbs lutein and zeaxanthin from eggs more efficiently than from plant sources because the fat acts as a carrier, dissolving these compounds so they can pass through your intestinal wall more easily.
What the White Contributes
Egg whites are mostly water and protein, with trace amounts of minerals like potassium and sodium. They contain almost no fat, no cholesterol, and very few calories (about 17 per white). If you’re eating whites only, you’re getting high-quality protein but missing the choline, vitamin D, vitamin A, lutein, zeaxanthin, and most of the B vitamins that make eggs nutritionally distinctive. The yolk is where the micronutrient density lives.
How Cooking Affects Nutrients
Heat doesn’t significantly reduce the mineral or choline content of eggs. Protein becomes easier to digest when cooked, so a cooked egg actually delivers more usable protein than a raw one. Some heat-sensitive vitamins like B12 and vitamin A decline slightly with cooking, but the losses are small with methods like poaching, soft-boiling, or scrambling over moderate heat. Frying at high temperatures for extended periods causes the greatest nutrient losses, though even fried eggs retain most of their nutritional value. The biggest variable in cooking is what you add: butter or oil increases the calorie and fat content, while boiling or poaching keeps the egg’s nutritional profile essentially unchanged.