What Does a Face Serum Do? Actives, Layering and Whether Price Matters
Serums explained: how they differ from moisturisers, what niacinamide, vitamin C, retinol and peptides each do, correct layering order and realistic results.
A serum is a lightweight, high-concentration treatment applied after cleansing and before moisturiser. Its job is to deliver active ingredients; a moisturiser's job is to hold water in and repair the barrier. They are not interchangeable.
The Main Actives and What They Do
- Niacinamide (vitamin B3): reduces redness, regulates oil, improves barrier function and fades post-acne marks. The Ordinary sells a 10% version for around $6 — one of the best value products in skincare.
- Vitamin C (L-ascorbic acid): antioxidant that brightens pigmentation and supports collagen. Unstable — buy in opaque packaging and replace once it turns orange.
- Retinol / retinoids: the most evidence-backed anti-ageing ingredient. Increases cell turnover, softens fine lines and treats acne. Start twice a week at night; expect 8-12 weeks before change is visible.
- Hyaluronic acid: binds water in the upper layers, giving immediate plumpness. Apply to damp skin and seal with moisturiser or it can dry the skin in low humidity.
- Peptides: signal molecules that support collagen production. Gentle, good for people who cannot tolerate retinol.
Layering Order
Cleanse, then thinnest to thickest: water-based serum, then oil or cream, then sunscreen in the morning. Vitamin C in the morning, retinol at night. Do not layer retinol with strong acids or benzoyl peroxide in the same routine unless a dermatologist told you to.
What About the $200-700 Creams?
Estée Lauder Advanced Night Repair ($130), Dior Capture Totale ($195), SK-II Facial Treatment Essence ($245) and La Prairie Skin Caviar ($690) all contain genuinely well-formulated ingredients — plus fragrance, texture engineering and a large brand premium. Above roughly $60 you are mostly buying formulation elegance and experience, not extra efficacy. A $10 retinol used consistently beats a $500 cream used occasionally.
Realistic Expectations
Hydration changes in days. Redness and oil control in 4-6 weeks. Pigmentation in 8-12 weeks. Fine lines in 3-6 months. Nothing topical replaces sunscreen, which is the single most effective anti-ageing product available.
Disclaimer
This content is for informational purposes only and does not constitute investment advice. You are advised to consult a qualified financial advisor before making investment decisions. USD Euro 360 makes reasonable efforts to ensure the accuracy of the information presented but cannot be held responsible for any losses.