"Vitamin C is a morning serum" — this statement is dogma in skincare circles. But is it really true?

The Function of Vitamin C

Vitamin C (ascorbic acid and its derivatives) has three main effects in skincare:

1. Antioxidant protection. It neutralizes free radicals; supports against UV and environmental stress.
2. Brightening. Regulates melanin production; reduces the appearance of dark spots.
3. Collagen synthesis. Acts as a cofactor in the skin's collagen production.

The Origin of the "Apply in the Morning" Claim

The first function — protection from UV — is the primary justification for morning use. Vitamin C supports the protection provided by sunscreen UV filters: SPF is the first line of defense, antioxidants are the second line of defense.

But Does It Also Work in the Evening? Yes.

All three functions of Vitamin C work regardless of the time of day it is used. Using Vitamin C in the evening is also a valid choice; especially if:

— There are no other actives like Retinol or AHA in your evening routine.
— You don't want to combine the SPF used in the morning with Vitamin C.

According to clinical data, what truly matters is consistent use. The question of morning or evening fades in comparison to the question of "do you use it every day?"

The Stability Issue

Pure ascorbic acid (L-Ascorbic Acid) loses its stability when exposed to light and air. Therefore, modern formulas use stable derivatives such as 3-O-Ethyl Ascorbic Acid, Sodium Ascorbyl Phosphate, and Ascorbyl Tetraisopalmitate.

Maxel JU Vitamin C Serum contains a combination of 3-O-Ethyl Ascorbic Acid + Sodium Ascorbyl Phosphate. These two stable derivatives do not degrade due to light or air; they provide consistent performance at any time of day.