Serums were originally manufactured for mature, ageing skin, but nowadays there are ones to protect against free radicals, banish wrinkles and sagging skin, moisturise, depigmentise, purify, desensitise, and more.

"Serums generally have a smaller molecular structure than creams or oils, and they penetrate deeper into the upper layer of the epidermis of the skin than other creams," explains Sandy Roy, owner and principal of the Beauty Therapy Institute in Cape Town.

"The pore structure of the skin enables this finely screened product to be absorbed far more effectively." It can be used all year, or you could use a serum as a booster treatment during the change of seasons.

"A more mature skin would definitely benefit from using serums all year round. However, switching serums could also give your skin a boost," says Sandy.

For younger skins, a desensitising serum might be recommended for particularly sensitive skin and a purifying and balancing serum for problematic skin.

As you get older and your skin matures, serums may be able to help you get a more youthful look without going under the knife.

With a serum, you can zone in on specific problem areas, such as the delicate eye-contour skin, where wrinkles, puffiness and discolouration show up easily.

There are many serums to choose from, so decide what you want to improve and investigate products to target that particular area. You should also ask your beauty therapist.

Serums tend to be expensive, but they are highly concentrated so you will use less. They're generally applied twice a day, unless indicated otherwise, after toning and before applying your moisturiser.

For night-time treatment