Morning c: morning c means using vitamin c skin care products in the morning, and evening a: evening a means using vitamin a skin care products at night. After all, we can't ignore the skin care problems of people with sensitive muscles. After all, the skin care method of "early C and late A" is more or less irritating. Using VC during the day can protect the light and reduce the damage to the skin; Alcohol A is photosensitive and will lose its activity under the action of ultraviolet rays, which will make the barrier more fragile, so it should be used at night. First of all, both vitamin C and vitamin A should gradually establish tolerance from low concentration. Once allergic phenomena such as redness and itching occur, you must stop using them and use anti-inflammatory repair ingredients in time.

Vitamin C is considered as an antioxidant. As a substance with strong antioxidant capacity, it has a good scavenging effect on free radicals produced by human body under unfavorable external conditions. VC is reductive, which can block the production of arginase and affect the production of melanin in the process of dopa forming melanin.

On the other hand, vitamin A is quite fragile. Afraid of oxidation and ultraviolet rays, it is easy to inactivate during the day and useless, but it is better to use it at night. Although these two ingredients are good, they are both irritating to some extent. Vitamin c is slightly less irritating, but it is enough to make people blush for sensitive muscles. Vitamin A, also known as retinol, has the functions of improving fine lines and wrinkles, shrinking pores and controlling and reducing oil secretion. The best is anti-aging, which can stimulate the regeneration of dermal cells and collagen.

However, all skin care work cannot be generalized. If you only talk about ingredients and ignore the formula and technology of products, and blindly pursue high efficiency regardless of your own skin condition, then "early C and late A" will not only make your skin rejuvenate, but also make you step on thunder, redness, allergies, peeling and even rotten face in minutes. Generally speaking, I personally prefer the combination of pre-C and post-A. If the skin is in a healthy state and there are students who need to fight aging, then you can start to act.