Office worker Li Xia likes to have a bowl of alkaline noodles with an egg for breakfast, but she only eats the white and discards the yolk each time, believing that eating the yolk can easily lead to weight gain. Many people do the same with their breakfast. So, is the yolk really useless?
It has become a consensus for most people that eating an egg for breakfast can not only improve memory but also protect vision and aid in weight loss. However, many people only eat the egg white and leave the yolk on the table or discard it, mistakenly believing that the protein in an egg is concentrated in the white, or worrying that eating the yolk will raise blood cholesterol and affect cardiovascular health. What they don't realize is that all the health-promoting components of an egg are in the yolk. The white is 88% water, potassium, and relatively pure protein. Almost all vitamins, trace elements, and health-promoting components like choline, betaine, lutein, and omega-3 fatty acids are in the yolk. If you eat the white and not the yolk, you lose the health benefits of eating an egg.
The yolk is rich in nutrients, as detailed below:
▲ The protein in both the yolk and the white is high-quality protein with high digestibility. However, the white is mainly composed of egg albumin, while the yolk contains not only rich egg vitellin but also abundant fat and micronutrients.
▲ The yolk is a complete nutritional food that supports life, containing all the vitamins and minerals needed by humans, including vitamin C.
▲ The yolk is rich in lecithin, sterols, as well as calcium, phosphorus, iron, vitamin A, vitamin D, and B vitamins, providing the necessary substances for brain development and normal function.
▲ The yolk contains a significant amount of cholesterol (an average of 250-300 mg per yolk), while the white has none. A 17-gram egg yolk contains only 256.7 mg of cholesterol. The Chinese Nutrition Society recommends a daily cholesterol intake of 300 mg per person, so there is no need to worry that eating one yolk will raise your cholesterol levels.
▲ The yolk provides a small amount of iron and is an important source of iron for ovo-lacto vegetarians.
▲ The yolk contains a small amount of omega-3 fatty acids, which is a nutritional deficiency for almost everyone (except the Inuit). It is crucial for maintaining human skin, nervous system, immune system, and hormonal system.
▲ The yolk provides vitamin B12, vitamin A, and vitamin D, which are nutrients that ovo-lacto vegetarians may lack.
▲ The yolk contains health-promoting components like zeaxanthin and lutein, which may help prevent and assist in treating human retinal macular degeneration and improve vision.
▲ The yolk contains all the nutrients needed to lower homocysteine, including vitamin B2, vitamin B6, vitamin B12, folic acid, zinc, and betaine. The higher the level of homocysteine in the body, the greater the risk of major diseases such as cancer, heart disease, and diabetes.
▲ The yolk promotes leptin secretion. Eating a yolk in the morning can significantly increase leptin levels in the body. Leptin is a hormone that inhibits fat synthesis, promotes fat breakdown, and helps control appetite.