Don’t know your hyaluronic acid from your retinol? We’re here to help demystify the skincare gobbledygook

Shopping for skincare isn’t easy – gone are the days of a simple three-step routine. Nowadays, it’s not just a case of making sure we’ve got the right cleansers, second cleansers, toners, mists, serums, masks, exfoliators, day moisturisers, night moisturisers, oils, and so on, but a case of knowing what is going on our skin. We want to get behind the labels and know the ingredients! But do you know what ingredients to look for? Or what everyone else is typing into their search bars?

Well, good news – we’ve done the research so you don’t have to and after a good nose around the data, established a list of the top five most-searched-for skincare ingredients in the UK. From the gold-standard that is retinol and the much-hyped hyaluronic acid to why everyone needs some vitamin C in their lives, this is everything you need to know, from what they do to how to use them.

The five skincare ingredients people searched for the most in the UK:

1. Vitamin C

2. Hyaluronic acid

3. Niacinamide

4. Retinol

5. Tea tree oil

Here’s the lowdown on each one…

Vitamin C

What: You’ll need to get your science hats on for this one. First and foremost, vitamin C is a preventative ingredient. To understand what vitamin C does, it’s important to understand the role of antioxidants in general (vitamin C is considered one of skincare’s most powerful).

Every day, our skin experiences ‘free-radical damage’. Essentially, free radicals are unstable molecules that can be created by our skin when it’s exposed to certain things. This kick-starts a process called oxidative stress. Oxidative stress can wreak havoc on our skin, from collagen fragmentation to pigmentation. One of the most common causes of free-radical damage is pollution. Antioxidants, such as vitamin C, can help prevent this process by helping to fend off free-radical damage. On top of this, vitamin C is widely considered to help increase collagen synthesis in the skin and support the reduction of the appearance of pigmentation. Ultimately, all of this means that vitamin C is ideal for helping to brighten for gorgeous, glowing skin.

Who: In theory, anyone can use vitamin C, but it’s thought to be particularly advantageous for those who experience skin pigmentation. However, depending on concentration, it can cause some skin to react and become sensitised.

How: Vitamin C products should be used in the morning to prevent free-radical damage throughout the day. It’s best applied directly to cleansed skin (it can be a very unstable ingredient and mixing it with other actives can turn it ineffective). As with all skincare actives, it’s advisable to start by applying once every few days and gradually increasing to every day in order to minimise the chance of irritation.

Try: Boots Vitamin C Brightening Moisturising Cream

• Size: 50ml

This lightweight cream can be used as a daily moisturiser to help hydrate skin and boost radiance at the same time.

Try: Garnier Vitamin C Micellar Water

• Size: 400ml

• Cruelty-free


Garnier’s micellar waters are some of the best products around when it comes to easy make-up removal. This particular formula contains vitamin C to help brighten while it works.

Try: Olay Vitamin C + AHA24 Day Gel Serum

• Size: 40ml

• Dermatologist-tested

When formulated into one product, vitamin C can be mixed with other beneficial ingredients, too. This serum also contains exfoliating alpha hydroxy acids to help dial up luminosity.

Hyaluronic acid

What: Confusingly, despite its name, hyaluronic acid isn’t an exfoliating acid. It is, in fact, an impressive skin hydrator. Hyaluronic acid is a naturally occurring molecule in our bodies that has moisture-retaining abilities. In the case of skin, it can help it attract essential moisture, giving it a plump, hydrated appearance.

Who: Anyone and everyone can use hyaluronic acid in skincare. Those looking for short-term hydrating, plumping and glow-boosting results will benefit the most.

How: Hyaluronic acid is mostly found in serums, masks, cleansers and moisturisers to help improve skin hydration. It can be applied morning and night. Results tend to be short-lived, so it’s advised to apply every day for best results.

Try: La Roche-Posay HyaluB5 Hyaluronic Acid Serum

• Size: 30ml

• Hypoallergenic

This no-fuss serum contains two different molecular weights of hyaluronic acid to help boost skin volume and plumpness at various levels.

Try: Boots Ingredients Hyaluronic Acid Serum

• Size: 30ml

• Vegan

• Not tested on animals

Hyaluronic acid products don’t have to be expensive. This simple vegan serum helps hydrate skin with none of the fuss.

Try: Estée Lauder Advanced Night Repair Serum Synchronized Multi-Recovery Complex

• Size: 50ml

• Oil-free

• Synthetic fragrance-free

• Non-acnegenic

Loved by skincare buffs all over the world, this little brown bottle contains a complex that helps deliver hydration thanks to its hyaluronic acid content, alongside glow-boosting and protective antioxidants.


What: Niacinamide is a form of vitamin B3, an essential nutrient praised for its skin-soothing benefits. However, niacinamide also has a host of other skin-loving properties, making it a great multitasker. Studies have shown that it has antioxidant benefits and it can help balance excessive, pore-enlarging sebum production (sebum being the oily substance produced by your body’s sebaceous glands).

Who: Our bodies do not naturally produce niacinamide, although most skin types can tolerate it well. Those with oily skin and prone to redness will likely benefit most from niacinamide in their skincare. In higher concentrations, niacinamide can sometimes cause irritation, so sensitive skin types should test the waters before diving straight in with daily application.

How: Because of its multi-use purpose and ability to be used morning and night, niacinamide can be found in a wide variety of skincare products. It’s most commonly found in serums and treatments, although can appear in lower concentrations in cleansers.

Try: The Ordinary Niacinamide 10% + Zinc 1%

• Size: 30ml

Containing both niacinamide and zinc, this affordable serum is formulated for oily, blemish-prone skin. It can help minimise the appearance of pores and aids in blitzing blemish-causing bacteria.

Try: CeraVe Foaming Cleanser for Normal to Oily Skin

• Size: 236ml

• Fragrance-free

• Non-comedogenic

Again, ideal for oily skin, this foaming cleanser features hydrating hyaluronic acid and ceramides to gently cleanse the face, as well as niacinamide to help tackle oil production and soothe any irritation.

Try: La Roche-Posay Effaclar Duo+ Blemish Treatment

• Size: 40ml

• Hypoallergenic

Dermatologists regularly recommend this treatment for oily and breakout-prone skin. It contains a blend of niacinamide, salicylic acid and zinc PCA to help improve the appearance of existing spots, unclog pores and control shine.


What: Retinol, which is a form of vitamin A, is regarded by many skincare experts to be the most effective skincare ingredient at helping to reduce the appearance of existing fine lines. However, it’s a potent ingredient, so it’s important to understand what it is and how it works before adding it into your routine.

‘Retinol or vitamin A is the only product that is proven to help boost the production of collagen and elastin. It has a wealth of benefits and is great for pigmentation, fine lines, wrinkles and acne, so can target many skin issues or be used for maintaining skin health,’ says Dr Deena, aesthetic doctor at The Well. It works by helping to increase the rate at which our skin cells naturally turn over. As a result, it can come with some sensitising side effects, such as redness, irritation, dryness and peeling, if not used correctly.

Who: Those with very sensitive skin should steer clear of retinol. ‘To ensure safety and mitigate irritation, it should be avoided in pregnancy and nursing, and by those with eczema, or other skin irritations,’ says Dr Deena. Similarly, younger people don’t need to add retinol into their routine. Most experts advise that, as a general rule, it’s an ingredient to start considering around your late twenties and early thirties, when the body’s natural collagen production starts to deplete.

How: ‘It does sensitise the skin so sun exposure should be avoided and the daily use of SPF is even more important to protect the skin,’ says Dr Deena. ‘Always apply at night. Start with a lower strength, once a week for two weeks, building to twice a week to ensure you phase this powerful ingredient slowly. Trialling multiple new active serums or new ingredients at the same time as vitamin A is discouraged.’ When using retinol, it may also be best to avoid exfoliating acids and enzymes, which can exacerbate irritation.

Try: Boots Ingredients Retinol Serum

• Size: 30ml

• Vegan

• Not tested on animals

This is a simple retinol serum that doesn’t contain a host of other active ingredients, making it a great way to dip your toe into retinol use.

Try: No7 Pure Retinol Eye Cream

• Size: 15ml

• Fragrance-free

The skin around the eyes is particularly delicate and sensitive, so we don’t recommend applying facial retinol products to the area. Instead, reach for a specially formulated eye cream, like this one, to minimise the risk of irritation.

Try: No7 Pure Retinol 1% Retinol Night Concentrate

• Size: 30ml
• Fragrance-free

One for the experienced retinol users out there – this powerful, high-strength formula aims to target the seven key signs of ageing to help make way for a youthful-looking complexion. Top tip: avoid layering this with other retinol products.

Tea tree oil

What: A far cry from some of the more high-tech ingredients on this list, tea tree oil is an essential oil that has been used in skincare for centuries. When applied topically, it’s thought to help reduce bacteria (that could potentially lead to breakouts) on the skin’s surface. As time’s gone on, its use for treating breakout-prone skin has become less recommended by skincare experts. Not because it doesn’t work, but because it can have irritating side effects, such as redness, dryness and peeling, if used in too high a concentration. However, it’s still a go-to for many for its spot-reducing abilities.

Who: Products containing tea tree oil should be mainly used by those with oily and less sensitive skin. Its drying effects make it unsuitable for those with particular dry or red skin. Similarly, if you have inflammatory acne, seek advice from a dermatologist or medical expert before applying tea tree oil.

How: To really reap the benefits of tea tree oil, it’s best used in products that contain low concentrations or as a targeted spot treatment. 

Try: Boots Tea Tree & Witch Hazel Spot Wand

• Size: 3.5ml

This handy spot wand can be used to dab the tea tree oil and witch hazel blend directly onto spots to help calm their appearance and reduce excess oil.

Try: No7 Advanced Retinol 1.5% Complex Night Concentrate

• Size: 30ml

No7 is widely considered to produce some of the best retinol products around, and this night concentrate contains a slow-release system to mitigate potential irritation.

Try: e.l.f. Oil Control Liquid Lotion

• Size: 65ml

• Suitable for vegans

Another lightweight hydrator, this lotion helps give oily skin a matte finish and is enriched with tea tree oil, niacinamide and kaolin clay.

For more skincare inspo, check out our ultimate guide to actives, layering and serums.