Serums contain a range of useful nutrients for your skin.
If you have blemish-prone skin, look for a serum with vitamin C, retinol, zinc, and salicylic acid.
Zinc can help soothe the skin, while salicylic acid can be helpful for unclogging pores.
If you are looking for a serum for dry skin, look out for vitamin E, niacinamide, glycolic acid, luminescine and hyaluronic acid.
Vitamin E is an antioxidant that can help protect skin from oxidative stress (an imbalance that can damage cells).
Glycolic acid is exfoliating, and hyaluronic acid retains moisture.
If your skin is feeling dull, look for serums with antioxidants.
To help reduce the appearance of fine lines or wrinkles, look for serums with retinol, caffeine, green tea, proteoglycans and hyaluronic acid.
For serums with retinol, try a small amount first as a tester (ie around 0.25%), and then you can go up from there.
For colour-correction like hyperpigmentation, uneven skin tone, dark spots, or enlarged pores, exfoliating serums and skin resurfacing can help. Look for phytic acid, kojic acid vitamin C, arbutin, azelaic acid, L-ascorbic acid and glycolic acid.
Serum can be applied after cleansing and before moisturising.
The reason for this is that moisturisers tend to be thicker and function like a barrier to help keep the active ingredients of the serum in.
Facial oils, on the other hand, go on top of the moisturiser because they have a bigger molecular structure. They keep the creams that have gone on first moist during the day.
Because of the concentration of ingredients in serums, they can occasionally cause irritation or dryness for people with sensitive skin.
Combat this by layering on a good amount of moisturiser after applying the serum (perhaps a bit more than you would normally use).
Use the serum as frequently as the label suggests, though once a day is typical, and store it in a cool dry place.
Some serums expire quickly because of the concentration of ingredients that can come in to contact with the air, so aim to use the product within six months to a year.