Vitamin C Serum: Benefits, Types and How to Use It

Vitamin C is an antioxidant used in skincare to support protection against environmental oxidative stress and improve the appearance of uneven tone and early photoaging. It works best as part of a complete morning routine, not as a replacement for sunscreen.

What vitamin C can do for skin

Topical vitamin C may help skin look brighter and more even over time. It also supports collagen-related processes and complements daily sun protection by neutralising some free radicals. Results depend heavily on the formula, packaging, concentration and regular use.

Vitamin C cannot erase pigmentation overnight or make sunscreen optional. Visible changes usually require weeks or months, and stubborn pigmentation may need professional assessment.

Pure vitamin C or a derivative?

L-ascorbic acid is the best-studied form, but it can be unstable and may sting sensitive skin. Derivatives such as ascorbyl glucoside are often easier to formulate and may feel gentler, although their clinical evidence and conversion in skin differ.

Choose by tolerance rather than chasing the highest percentage. A lower-strength, well-packaged product used consistently may be more useful than a strong serum that repeatedly irritates the skin.

How to use vitamin C serum

1. Cleanse gently and pat the skin dry.
2. Apply a few drops of vitamin C serum.
3. Follow with moisturiser.
4. Finish the morning routine with broad-spectrum SPF 30 or higher.

Start three or four mornings per week if your skin is reactive. Increase only when the routine remains comfortable. Follow the product label because textures and directions vary.

Can vitamin C be used at night?

Yes. Morning use is popular because it fits naturally under sunscreen, but a stable formula can also be used at night. The best time is the one that makes consistent, irritation-free use easier.

What can be layered with vitamin C?

Vitamin C commonly sits well with moisturising ingredients such as hyaluronic acid, ceramides and niacinamide. Using it in the same routine as exfoliating acids or retinoids can be too irritating for some people. Separate strong actives by time of day or alternate nights when needed.

Signs the product has oxidised

A clear or pale serum that becomes deep orange or brown, develops an unusual smell, or changes texture may have oxidised. Store it tightly closed, away from heat and direct light. Do not keep using a formula that has changed substantially.

Verified Skinora options

• The Ordinary Ascorbyl Glucoside Solution 12%
• The Ordinary Vitamin C Suspension 23% + HA Spheres 2%

The suspension is a strong, textured formula and may not suit a beginner. Check the live product page for current availability and directions.

When to stop

Persistent burning, swelling, a rash or worsening redness is a reason to stop. Introduce one new active at a time so the cause of irritation is easier to identify.

Continue with Skinora

• Niacinamide for skin
• Sunscreen before or after moisturiser?
• How to repair a damaged skin barrier

Sources

• Systematic review of topical vitamin C in melasma and photoaging
• American Academy of Dermatology: skincare in your 20s