VC is only sensitive to light and is easily oxidized by free radicals caused by ultraviolet rays, sacrificing itself to protect the skin from oxidation. This is called “poor photostability” of VC. Most VC derivatives do not have this problem. With current formula technology, even prototype VC can be used during the day as long as the formula is properly protected.
Is the whitening effect reduced if you use VC during the day?
Using VC in the morning is beneficial and effective for anti-aging and anti-oxidation. However, in order for VC to exert its whitening effect, it needs to be interfered with by free radicals as little as possible so that it can be more involved in the action of inhibiting melanin synthesis, so it is more appropriate to use it at night.
VC oxidizes and turns yellow, so it can’ t be used?
VC can be used after it is oxidized and turns yellow. This is mainly due to our skin’s own redox system. After the oxidized and yellowed VC enters the skin, it will be reduced to VC by the skin’s redox system (such as glutathione, etc.).
Can Niacinamide and VC be used together?
Theoretically, they can be used together, but in actual use, it still needs to be judged according to your own skin type. Considering that both ingredients may cause irritation, people with tolerant skin can try to use them together.