The interval between blood donations should be no less than 6 months in order for the red blood cells in the body to recover. China advocates voluntary blood donation for healthy citizens between the ages of 18-55. Each blood donation should be 200-400ml, and the interval between donations should not be less than 6 months. Healthy people have strong hematopoietic capacity, and the recovery time of plasma, white blood cells and platelets lost when donating blood is short, usually about 1 month to the level before donation. Red blood cells, on the other hand, recover more slowly and take 3-4 months to gradually return to their pre-donation levels. Blood donation does not affect the health of healthy people and can stimulate bone marrow production. Before donating blood, you should avoid taking medications, drinking alcohol and eating too oily food, and women should avoid menstruation. After blood donation, you should take iron-rich foods, such as beef, mutton, pork and other red meat, and various blood products.