Melatonin is a hormone secreted by the pineal gland of the brain that makes a type of melanin-producing cell glow, hence the name melatonin. It has nothing to do with reducing melanin in the body or brightening the skin, and cannot lighten the skin. Melatonin is an endogenous hormone that is secreted by the pineal gland in the mammalian brain and works through the regulation of the endocrine system. Studies have shown that melatonin regulates the body’s biological clock. When a person senses a drop in ambient light, the pineal gland begins to secrete trace amounts of melatonin, informing the body that it needs to enter a restful sleep state, and the body begins to feel sleepy. According to the latest research findings, melatonin has the effect of improving sleep, delaying aging and fighting tumors, but has no skin whitening effect. If you want to make your skin white, you need to pay attention to the following matters: 1, pay attention to sun protection: when you go out, you should take protective measures, such as wearing a hat, umbrella, sunglasses or apply sunscreen preparations, etc.; 2, pay attention to diet: food has a greater impact on the skin, eat more vegetables and fruits rich in vitamin C, which is good for whitening skin, such as tomatoes, strawberries, kiwi, etc.; 3, pay attention to rest: lack of sleep not only affects health, but also slows down skin blood flow. It will also slow down the blood flow to the skin, vascular constriction, blood stasis into spots, and the skin becomes gray-black. Therefore, it is important to pay attention to proper rest and adequate sleep.