Hyaluronic acid is one of the most accessible skincare ingredients on the market, and many professional and consumer products are formulated with it.
In the third instalment of our acids series, we speak to some of the skincare experts to find out more about its benefits and how it can be used in skincare routines and treatments.
What is hyaluronic acid?
Hyaluronic acid is a carbohydrate compound (more specifically, a glycosaminoglycan) which occurs naturally in the body – the average person has 15 grams of it, a third of which is degraded and replaced daily.
It has several important functions including aiding in wound repair, cell adhesion and joint lubrication. Although hyaluronic acid is present in the skin, it is often supplemented topically with skincare products.
While you might associate the word “acid” with stronger ingredients like glycolic and salicylic acid, hyaluronic acid’s name actually comes from the “hyaluronic acid synthase” enzyme which produces hyaluronic acid.
Unlike its harsher acidic cousins, hyaluronic acid doesn’t exfoliate the skin, instead acting as a humectant – a hydrophilic, or water-loving, substance which attracts water. Hyaluronic acid’s presence in the skin helps to keep it hydrated.
“It works like a sponge – pulling moisture from the air into your skin,” explains CACI trainer Sarah-Jane Morris. In fact, hyaluronic acid is capable of holding over 1,000 times its weight in water.
The ability to supplement the body’s natural hyaluronic acid is important because, as with most skin components (looking at you, collagen), the body’s creation of hyaluronic acid starts to slow down from the age of 25. The hyaluronic acid used in skincare is synthetic – it can be created in a lab through the fermentation of glucose and yeast extract.
Although this all sounds promising, topical hyaluronic acid does have its limitations. It tends to have a large molecular size which prevents it from penetrating through to the dermis, meaning it can’t usually provide more than superficial hydration on the skin’s surface.
However, some higher end products contain hyaluronic acid of a few different molecular weights which “will affect the delivery and depth of the absorption” through the skin’s layers, according to Rebecca Jones, a trainer and ambassador for Noon Aesthetics.
How does hyaluronic acid help the skin?
Hyaluronic acid has a number of benefits, including:
- Hydration: Hyaluronic acid’s ability to attract moisture from the air to the skin means it’s great for treating dehydrated skin. “We are all prone to dehydration from internal and external factors, so hyaluronic acid is a vital water source for the skin,” explains Jones. However, “dry or sensitive skin will also require oils to nourish and replenish lost lipids”, according to Lesielle UK lead educator Jon-Paul Hoy.
- Protecting the skin: Hyaluronic acid can help repair a compromised skin barrier, or stratum corneum, by pulling water from the air and dermis towards the epidermis. “It can calm skin reaction with its barrier-balancing effects, as well as regulating oil production and reducing shine, supporting youthful skin function and smoothing the surface instantly,” says Jones.
- Plumping effects: “Hyaluronic acid is native to the dermis of the skin, helping to balance water content, but it also has structural properties – it helps the skin look plump and bouncy,” adds cosmetic doctor Catharine Denning, who runs a regular clinic from The Light Centre, London. As mentioned, the hyaluronic acid would actually need to penetrate through to the dermis to have a real plumping effect.
Is hyaluronic acid good for all skin types?
Hyaluronic acid is suitable for all skin types and concerns, but Morris says it’s “particularly beneficial for drier and more mature skins” where extra hydration is needed.
Sensitivity and reactivity are far more of a concern for the likes of vitamin C and retinoids, but it is still a possibility with hyaluronic acid. “Very rarely, someone may be allergic to topical hyaluronic acid, but this is highly unlikely,” says Denning. “Injectable or ingested forms would require a discussion with a medical professional before using.”
How should you use hyaluronic acid?
Hyaluronic acid is available in standalone serums, but because it’s a stable ingredient it can also be found in combination with other ingredients in many products – either as hyaluronic acid or sodium hyaluronate, its salt form.
“Hyaluronic acid is suitable for all skin types and is a relatively benign, unreactive ingredient,” says Denning. “For pure humectant hydration, it is often mixed with sodium pyroglutamic acid (PCA), which works synergistically to draw even more water into the skin's layers.
“It’s also a great vehicle to be used alongside peptides and vitamins in skincare, which can supercharge your skin health.”
Retinoids are a great pairing with hyaluronic acid. Tracy Tamaris, co-founder of IIAA, explains, "Vitamin A naturally increases our hyaluronic acid production by stimulating the fibroblast cell membrane receptors (CD44). Applying hyaluronic acid topically will also stimulate our fibroblast cells to produce more hyaluronic acid naturally."
Hyaluronic acid can be used topically in skin serums and moisturisers to help with superficial hydration. It’s best used on slightly damp skin to aid moisture absorption, so clients might want to use it directly after cleansing or using a face mist.
Hyaluronic acid can also be worked into a more extensive skincare routine. “I always advise its use in a daily routine following cleansing, exfoliating and any active ingredients such as vitamin C or retinoids,” explains Denning.
“The reason for this is that the hyaluronic acid molecule is relatively large so if you apply it before active ingredients, it often blocks other ingredient absorption.
“If you are using a standalone, pure hyaluronic acid serum (not mixed with other ingredients), I would follow with a heavier emollient, ceramide-rich moisturiser for dry or sensitive skin – and, of course, don't forget to apply sunscreen at the end of your routine every morning, come rain or shine,” Denning adds.
Along with being a common ingredient for clients to use at home, hyaluronic acid is an industry favourite in professional beauty treatments. “It supports all facial treatments from gentle wellbeing facials to the most ablative skin treatments, such as needling, peeling, laser and light therapies,” says Jones.
“It helps to promote skin healing after treatments because hyaluronic acid and water are much-needed ingredients in the wound-healing process, helping to support collagen fibre networks post injury to prevent scarring.”
Tamaris comments, "It can also be used in salon treatments together with enhanced penetration techniques such as low frequency ultrasound and pulsed iontophoresis for maximum results."
Hyaluronic acid is also used in more invasive aesthetics treatments. Dennings says, “Hyaluronic acid has become really popular among cosmetic doctors in the last few years because it can be injected deeper into the skin in the form of skin boosters and soft tissue fillers to help restore the structural component of the dermis. There are also ingested forms of hyaluronic acid, which are used primarily by those with joint pains or injury.”
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