Serum
Serum — how to choose
A serum is the step that does the work. Cleansers clean, moisturisers seal, and sunscreen protects — but the serum is where the active ingredients live, at concentrations high enough to change how your skin looks over weeks.
It goes on after toner and before cream, on skin that is still slightly damp. Three or four drops is enough for the whole face; using more does not make it work faster.
Choosing a serum
For dullness and uneven tone — look for niacinamide, usually at 5–10%. Anything higher can sting on sensitive skin. If you have marks left behind after blemishes, tranexamic acid works on those specifically and most brightening actives do not.
For dehydration — hyaluronic acid holds water in the upper layers. Apply it to damp skin and seal it with cream, or it will pull moisture from the air in dry weather and leave you worse off.
For sensitivity and redness — centella asiatica is the standard, and it is the base of SKIN1004's entire range. Fermented versions absorb further because fermentation breaks the extract into smaller molecules.
For firmness — peptides and PDRN. Both work slowly. Judge them after two months rather than two weeks; anything promising faster is overselling.
For texture and fine lines — retinol. Start at 0.2%, twice a week, and never skip sunscreen. Most retinol attempts fail because people start too strong and give up when their skin flakes.
Using more than one
You can layer serums, thinnest first, waiting a minute between. What you should not do is combine strong actives on the same night — retinol with acids, or two exfoliants. If you want both, alternate nights.
Frequently asked
How long before I see a difference?
Hydration shows immediately. Tone takes four to six weeks. Firmness takes two to three months. Anyone promising faster is selling you something.
Can I use a serum without a moisturiser?
On oily skin in summer, sometimes. Most of the time no — a serum delivers actives but does not seal them in, and the water it draws up will evaporate.
Morning or evening?
Antioxidants like vitamin C in the morning, retinol always in the evening. Everything else works either time.
Do I need a serum at all?
If your skin is comfortable and you have no specific concern, no. Cleanser, moisturiser and sunscreen is a complete routine. A serum is what you add when there is something specific you want to change.
