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Egg yolk

Gallus gallus domesticus

Also known as Yolk, Egg yellow

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The fat-soluble half of the egg, carrying essentially all of its fat, cholesterol, fat-soluble vitamins, choline and carotenoid pigment. Its colour tracks the hen diet rather than nutritional quality in any simple way.

Heart HealthEye HealthWomen's Health

Potential health benefits

Best supported: Limited

Ordered by how well the human research supports them — strongest first. A rating describes the state of the evidence, not how impressive the food is. How we rate evidence.

Blood lipid profile

Heart Health
Limited evidence

Research suggests yolk intake raises both LDL and HDL cholesterol modestly, with a wide spread of individual responses. The clinical meaning of that pattern is still argued over.

Limited evidence. Early human work, or mostly lab and animal research.

3 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Macular health

Eye Health
Limited evidence

Some trials report increases in macular pigment optical density when egg yolks are added to the diet. Studies are small and short, and whether that translates to eye outcomes over years has not been shown for eggs specifically.

What may be going on: Yolk lutein and zeaxanthin sit in a lipid matrix that appears to be absorbed more readily than the same carotenoids from leafy greens.

Limited evidence. Early human work, or mostly lab and animal research.

3 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Pregnancy nutrition

Women's Health
Limited evidence

Has been studied as a dietary source of choline, a nutrient with established requirements that rise in pregnancy and lactation and that most pregnant people fall short of. Trials of choline supplementation and infant outcomes are small and mixed.

Limited evidence. Early human work, or mostly lab and animal research.

2 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

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Key nutrients

Nutrient content per 100 grams
NutrientAmount% DV
Macronutrients
Calories322 kcal16%
Protein15.9 g32%
Total fat26.5 g34%
Carbohydrate3.59 g1%
Fibre0 g0%
Total sugars0.56 g—
Water52.3 g—
Fats
Saturated fat9.55 g48%
Monounsaturated fat11.7 g—
Polyunsaturated fat4.2 g—
Cholesterol1085 mg362%
EPA (omega-3)0.011 g—
DHA (omega-3)0.114 g—
DPA (omega-3)0 g—
Linoleic acid (omega-6)3.54 g—
Vitamins
Vitamin A381 µg42%
Vitamin C0 mg0%
Vitamin D5.4 µg27%
Vitamin E2.58 mg17%
Vitamin K0.7 µg1%
Thiamin (B1)0.176 mg15%
Riboflavin (B2)0.528 mg41%
Niacin (B3)0.024 mg0%
Pantothenic acid (B5)2.99 mg60%
Vitamin B60.35 mg21%
Folate146 µg37%
Vitamin B121.95 µg81%
Choline820 mg149%
Minerals
Calcium129 mg10%
Iron2.73 mg15%
Magnesium5 mg1%
Phosphorus390 mg31%
Potassium109 mg2%
Sodium48 mg2%
Zinc2.3 mg21%
Copper0.077 mg9%
Manganese0.055 mg2%
Selenium56 µg102%
Other measured compounds
Beta-carotene88 µg—
Alpha-carotene38 µg—
Lycopene0 µg—
Lutein + zeaxanthin1094 µg—
Caffeine0 mg—
Ash1.71 g—

Nutrient values are per 100 g of the USDA reference entry named on this page and vary with variety, growing conditions, storage and preparation.

Source record: Egg, yolk, raw, fresh (USDA FoodData Central, FDC ID 172184).

% DV uses the FDA Daily Values for adults and children aged 4 and over. A dash means no Daily Value has been established for that nutrient.

Bioactive compounds

Compounds present in meaningful amounts. Presence is banded rather than quantified, because whole-food levels vary enormously with variety, growing conditions, storage and preparation.

How preparation changes things

Only effects with real support are listed. If a preparation method is missing, it is because nothing dependable is documented — not because it makes no difference.

  • with fatIncreases carotenoid absorption from other foods

    Adding egg yolk to a salad measurably increases absorption of carotenoids from the vegetables eaten with it, because the yolk lipid helps form the mixed micelles carotenoids need.

Things to know

Allergies, interactions and intake concerns. Every food gets this section — a reference where everything is uniformly good is not a reference.

  • Allergy

    Egg allergy

    Yolk carries fewer of the dominant allergens than white but is never fully separable from it in practice, so it is not a safe alternative for someone with egg allergy.

  • Worth knowing

    Raw yolk and Salmonella

    Raw yolk preparations such as homemade mayonnaise, tiramisu and carbonara finished off heat carry Salmonella risk, which matters most in pregnancy, infancy, older age and immunosuppression.

  • Worth knowing

    Concentrated dietary cholesterol

    All of the cholesterol in an egg sits in the yolk. Population-level effects are modest, but people identified as hyper-responders and those with existing cardiovascular disease are still advised to moderate intake.