Heat preservation and hydration will never rebound. It is not a functional product. For example, whitening products will rebound more easily if they are not maintained. Like younger people, basically under 20 years old, or around, you can hydrate, because you only have enough water to replenish, then your skin is not prone to problems. Like dry skin, if the water is not enough, the face will be darker and yellower, and it is easy to grow spots. Oily skin is prone to acne and has a shiny face. Only by supplementing enough water can the skin achieve water-oil balance. Will appear transparent, white and beautiful.