The effects of egg yolk: 1, can improve the level of vision, relieve visual fatigue, because the egg yolk is rich in vitamin A, and vitamin A constitutes an important raw material for the retinal photoreceptors, appropriate eating egg yolk supplement vitamin A, in improving the level of vision, relieve visual fatigue role is very obvious. 2, can provide the body with rich vitamin D, and vitamin D can well promote the intestinal mucosa on the absorption of calcium, can also promote the kidney tubules on the absorption of calcium, in improving the utilization of calcium absorption is very obvious. It can also promote the absorption of calcium by the kidney tubules, which has a very obvious role in improving the utilization rate of calcium absorption. Properly eating egg yolk supplemented with vitamin D to promote calcium absorption has a very strong role in preventing osteoporosis and preventing lumbar and knee weakness and lumbar and leg pain.