People of the older generation often like to talk about sunbathing. The quilt should be sunburned to prevent mites, flowers and plants should be sunburned to be able to not wither, people should also be sunburned to be able to replenish calcium, to grow taller, to sleep well at night. In fact, sunshine is not the same as calcium supplementation. The sun can indeed promote the formation of vitamin D, help the body absorb dietary calcium, phosphorus and other substances, can play a role in preventing rickets, osteoporosis, and can even kill the bacteria on the skin. But as with medication, it is not advisable to talk about toxicity without the dose, and it is not advisable to say that the sun is good, but ignore the hidden dangers. Why do Europeans and Americans have a very high incidence of skin cancer? The ultraviolet rays from the sun can cause malignant changes of skin pigment cells and eventually lead to skin cancer. For example, when I was studying in the United States, a professor in our laboratory was found to have body cell cancer, which was then surgically removed. Especially for us northerners, we have a special emotion for the sea since childhood. Often, we went to the seaside in the south to play and forget about it. At that time, although we also felt the sun in the water soaking, we did not feel much pain. After a few days, the body, the back began to serious violent skin, many people also began to go to the dermatology department to seek treatment. For the light, the first is the violent skin, the second item when it comes to discoloration. Many women go to the mountains and the sea for a trip and come back with discoloration, which is getting heavier and heavier, and even blistering after sunburn. The original age spots, which have some bad lesions, even affect the health of the body, must be considered to be removed. Therefore, moderate sun exposure is good for health, but it does not mean that more is better. When sunbathing, we should pay attention to protect our skin, apply a sunscreen, play a sunshade, or wear a sun hat, and try to avoid the direct sunlight, all are good skin care methods.