The benefits of egg yolk: 1, can provide the body with rich vitamin A, and vitamin A constitutes an important raw material for the retinal light-sensitive substances, appropriate eating egg yolk supplement vitamin A, in improving the level of vision, especially the level of dark vision, to relieve visual fatigue is very obvious benefits. At the same time, vitamin A can also prevent hyperkeratosis of the skin mucosa and make the skin smoother and more delicate.2. It can provide the body with abundant vitamin D, which can well promote the absorption of calcium by the intestinal mucosa and the back absorption of calcium by the kidney tubules. Therefore, by eating egg yolk to supplement vitamin D, the benefits in preventing osteoporosis and preventing back and knee weakness are very obvious.