Guide
What does a serum do and how do you choose one?
Serums are light, fast-absorbing products that carry a high concentration of active ingredients aimed at a specific skin concern. If cleanser and sunscreen are "for everyone", serum is the step that is "for your goal": dark spots, acne, dryness or fine lines.
Where it fits in your routine
- Cleanse
- Tone
- Treat
- Moisturize
- Protect
Serum vs moisturizer
Moisturizers are richer products made of oils and humectants that keep the skin hydrated. Serums usually carry a higher concentration of actives in water or a light base and spread over the skin faster.
That is why a serum rarely replaces moisturizer. A light moisturizer may be enough for oily skin, but applying a moisturizer after your serum also balances the drying or irritating effect of the active.
Which serum for which concern?
- Oiliness, visible pores, uneven tone: niacinamide serum
- Dullness, sun spots and antioxidant protection: vitamin C serum in the morning
- Fine lines, texture and acne: retinol at night, or bakuchiol as a gentler alternative
- Dehydrated, tight-feeling skin: hyaluronic acid serum
- Stubborn dark spots and melasma: serums with alpha arbutin, tranexamic acid, azelaic acid or kojic acid
- Sensitivity and redness: soothing serums with centella asiatica, panthenol and ceramides
What to look for when buying
- Choose your goal first, then the active: there is no serum that "does everything"
- A stated percentage; moderate strengths to start with (e.g. 5% niacinamide, 0.2–0.3% retinol)
- Dark, pump or airless packaging for vitamin C and retinol
- A fragrance-free formula for sensitive skin
- Not getting the same active from two different products in one routine
How to use it
After cleansing, and toner if you use one, take two or three drops of serum in your palm and press it over your face and neck. Wait a few seconds for it to absorb, then apply your moisturizer. In the morning, do not forget sunscreen after your serum.
Start a new serum on its own and use it consistently for at least four to six weeks; the results of most actives are not clear before then. Introduce strong serums such as retinol or acids two or three evenings a week and increase the frequency slowly.
If you use two serums, apply them from thinnest to thickest and keep strong actives apart: vitamin C in the morning, retinol at night. Do not layer retinol and an acid serum on the same night.
Common mistakes
- Starting three or four strong serums at the same time
- Giving up after two weeks
- Using an opened vitamin C serum until it turns dark: a product that has turned deep orange has lost its effect
- Starting with high-strength products and irritating your skin
- Neglecting sunscreen while using serums
FAQ
How many serums can I use together?
For most people, one serum in the morning and one at night is enough. More than that raises the risk of irritation and makes it harder to tell which product is working.
Can a serum replace moisturizer?
Usually not. Some oily skin can get by with a hydrating serum alone, but for most skin types a moisturizer after serum protects the barrier.
How long does a serum take to work?
Humectants such as hyaluronic acid are felt immediately. Niacinamide, vitamin C and dark spot serums usually take 6–12 weeks, and retinol 8–12 weeks or more of consistent use.
Can I use niacinamide and vitamin C serums together?
Yes. The idea that they cannot be combined is an old myth. You can layer them in the same morning or use one in the morning and the other at night.
This article is for general information only and is not medical advice. If you have a skin condition, are pregnant or take regular medication, talk to your dermatologist or pharmacist before starting a new product.
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