Egg yolk is rich in vitamin A, vitamin D and vitamin E, as well as minerals such as iron, calcium and zinc. It is also an important source of cholesterol and saturated fats, so it is recommended to consume it in moderation. Egg yolk is often used in the kitchen for its creamy texture and for its ability to link the ingredients in pastry recipes. It is also commonly used as a base of sauces, mayonnaises and dressing.