The egg yolk is the yellow part located in the center of the egg. It is high in cholesterol, but also provides a host of essential nutrients and health benefits. Eggs are inexpensive, nutrient-dense foods that are easy to find and prepare, making them an excellent staple for many people around the world. They are extremely versatile. People can prepare eggs in many different ways or use them in many aspects of food preparation, cooking, and baking.
In this article, we explain the benefits and nutritional composition of egg yolk. We also compare them to egg whites and provide tips on how to consume them safely.
Benefits of egg yolk
Eating the egg white and yolk together in a whole egg provides the right balance of protein, fat, and calories. This combination makes most people feel fuller and more satisfied following eating eggs in meals. However, one study suggests that most of an egg’s nutrients are found in the yolk. The distribution of proteins, on the other hand, is homogeneous throughout the egg.
This study highlights several benefits that egg yolk nutrients and protein can provide, including:
Lower risk of gastrointestinal upset: This benefit may be due to egg yolk proteins, such as phosvitin, which may reduce the number of compounds in the body that cause inflammation.
A strengthened immune system: Certain compounds called sulfated glycopeptides are present in the egg yolk membrane. They can stimulate the production of macrophages, immune system cells that protect the body once morest disease and infection.
Lowering blood pressure: The review notes that egg yolk contains several compounds called peptides that research has shown to significantly reduce blood pressure in rats.
High blood pressure is a risk factor for cardiovascular disease.
Reduced risk of vision problems: The American Heart Association states that egg yolk is an important source of lutein and zeaxanthin. These carotenoids may protect once morest cataracts and macular degeneration, two common eye problems that often develop following age 55.
It should be noted that many of the studies presented in this review did not test the effects of egg yolk in humans. Instead, they performed the tests in the laboratory or on animals. Therefore, the results may not apply to humans. Researchers have also begun to explore the potential of various immunostimulants called immunoglobulins, which are present in egg yolks.
For example, a 2017 study found that female mice were less likely to become infected with Helicobacter pylori, bacteria that commonly cause intestinal infections, following consuming anti-VacA IgY, an immunoglobulin found in the yolk of egg.
Egg yolk nutritional information
Cooking eggs in oil increases the fat content of a dish. The nutritional content of an egg yolk depends on the size, origin and processing of the egg, as well as the species from which it comes.
The final dietary value of egg yolk varies greatly depending on its preparation. For example, cooking whole eggs in oil can double or even triple the fat and cholesterol content of an egg dish.
The raw yolk of a standard large egg provides the following:
55 calories
2.70g protein
4.51 g fat
184 milligrams (mg) of cholesterol
0.61g carbohydrates
0.10 g of sugar
0g dietary fiber
Egg yolk contains at least seven essential minerals, including:
calcium
fer
magnesium
phosphorus
potassium
sodium
zinc
Egg yolk is an abundant source of many vitamins, including fat-soluble and water-soluble vitamins.
The table below shows the vitamin content of one large egg yolk (17 g).
Thiamine 0,030 mg
Riboflavine 0,090 mg
Niacine 0,004 mg
Vitamine B-6 0,060 mg
Vitamin B-12 0.332 micrograms (mcg)
Vitamin A 64.8 mcg
Vitamine E 0,439 mg
Vitamin D (D-2 and D-3) 0.918 mcg
Vitamin K 0.119 mcg
Duck, quail, goose and turkey eggs contain higher amounts of many essential nutrients than chicken eggs.
Egg yolk or egg white
The yolk of a large egg contains 2.7 g of protein, while the white contains 3.6. While the white provides more protein, the yolk contains almost all of the fat- and water-soluble vitamins and minerals of eggs. Research suggests that eating whole eggs has greater benefits than eating egg whites alone. For example, a 2017 study found that young men who ate whole eggs immediately following performing resistance exercise had higher muscle metabolism rates than those who ate only egg whites.
Considerations
Buying eggs from a reputable seller can reduce the risk of food poisoning. The most common egg-related health problem is food poisoning from Salmonella bacteria, which poultry naturally carry. These bacteria can contaminate the eggs. Salmonella infections can be serious, especially for young children, people with immune disorders, and people over the age of 65. However, following a few basic precautions when buying, storing, handling and cooking eggs greatly reduces the risk of food poisoning.
Here are some tips for handling eggs safely:
make sure the eggs have no cracks or holes in the shell before you buy them
washing hands and all exposed surfaces with soap and water immediately following coming into contact with raw eggs
eat or refrigerate eggs no later than two hours following cooking them
cook eggs until at least the whites are firm (those at high risk of infection should cook eggs until the white and yolk are firm)
cook egg dishes, such as quiches, to an internal temperature of at least 71.1°C
cook scrambled eggs until firm
discard broken, dirty or cracked eggs, as well as expired eggs and egg products
avoiding eggs that are odd in consistency, appearance, or smell
keeping raw eggs away from other foods, especially foods that don’t require cooking
Résumé
The egg yolk and white are most nutritious when eaten together as part of a whole egg. Most of the nutrients in an egg are present in the egg yolk. Results from laboratory studies suggest that certain compounds in egg yolk may help prevent gastrointestinal upset, boost immune function and lower blood pressure. However, more human studies are needed to confirm these potential benefits. Eggs also carry a risk of Salmonella infection if a person does not store and prepare them properly. Maintaining good hygiene when preparing eggs is essential to prevent food poisoning.
