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Vitamin C

What is vitamin C in skincare? Vitamin C is a powerful antioxidant that helps neutralize free radicals, even out skin tone, reduce pigmentation, and boost collagen production.

How to use it

The effectiveness of vitamin C depends on its form, concentration, and packaging. Here’s what to keep in mind when choosing a product:

• L-Ascorbic Acid is the most studied and effective form. Works well but can be unstable and sometimes irritates sensitive skin.

• Derivatives (like Ascorbyl Glucoside, Sodium Ascorbyl Phosphate, Tetrahexyldecyl Ascorbate) are more stable and gentler forms. Better for sensitive skin and longer shelf life.

• Effective concentrations usually range from 5% to 20%, with 8% or higher considered most effective.

Suitable for

All skin types, especially aging or dull skin.

Things to know

Vitamin C pairs well with vitamin E and hydrating ingredients.

Avoid combining niacinamide with the acidic form of vitamin C (ascorbic acid), as this may cause redness. Combining glycolic acid with the acidic form of vitamin C (ascorbic acid) may also lead to a strong reaction.

FAQ

1. Can vitamin C be used with peptides?

Yes, vitamin C and peptides can be used together, and in many cases this combination is considered beneficial for anti-aging skincare. However, the vitamin C in the form of L-ascorbic acid works effectively only at a low pH (around 3-3.5). At the same time, most peptides are unstable in an acidic environment and may break down. When mixed in one product or applied one after another, the effectiveness of peptides may decrease. So, if a product contains L-ascorbic acid, it’s better to apply peptides at a different time. Alternatively, choose vitamin C derivatives (such as magnesium ascorbyl phosphate, tetrahexyldecyl ascorbate, or sodium ascorbyl phosphate). They work at a neutral pH and don't damage peptides.

2. Is vitamin C anti-aging?

Yes, this is one of the vitamin C benefits: it's a powerful antioxidant and helps stimulate collagen production. However, it works more as a preventive ingredient.

3. Does vitamin C exfoliate the skin?

Vitamin C is an antioxidant and doesn't exfoliate the skin. Still, L-ascorbic acid at concentrations of 15% or higher and below pH 4 can act as an exfoliant.