We’ve all heard that hyaluronic acid can hold 1,000 times its weight in water, but polyglutamic acid, which remains a relatively quiet skincare hero, holds more. And depending on which source you believe – up to five times more.
“Polyglutamic acid has very recently been picking up steam in the industry due to its powerhouse hydration capabilities,” says the superstar aesthetician Kate Somerville.
Polyglutamic acid (PGA) is a naturally derived peptide that is seriously hydrating, so it can reduce the appearance of lines by plumping up skin and improving elasticity, as well as giving serious glow.
It has a higher molecular weight than hyaluronic acid, but this means it delivers surface-level hydration, rather than penetrating deeply into the skin.
You might find it listed as polyglutamic acid, sodium polyglutamate or just polyglutamate; they’re all the same thing, but with some variation in how it’s formulated.
It’s no replacement for hyaluronic acid, but rather a brilliant companion for it. Together the two offer deep and surface hydration. “Polyglutamic acid works very well partnered with hyaluronic acid,” says Somerville. “The combined usage amplifies their separate benefits.” You’ll find the two together in the ingredient lists of many of our picks.
PGA even helps your skin produce more hyaluronic acid naturally. “[It] inhibits the action of hyaluronidase, the enzyme that breaks down hyaluronic within the skin. This increased reservoir of hyaluronic results in a more youthful skin appearance,” adds Somerville.
While there hasn’t been anywhere near as much noise made about PGA as there has been about other hero ingredients, you’ll find it quietly listed in the ingredients of many brilliant formulas, from eye creams to serums.
We’ve been testing them to discover the hydrating powers of PGA for ourselves; these are our favourites.
You can trust our independent reviews. We may earn commission from some of the retailers, but we never allow this to influence selections, which are formed from real-world testing and expert advice. This revenue helps to fund journalism across The Independent.
Oskia isotonic hydra-serum
Best for: Dry skin
Nothing we’ve ever tried has improved the condition of our dry skin like Oskia’s Isotonic serum. The brand’s products are formulated with bio-available or cellular nutrients and actives that are like nutrition for the skin, helping it be the best version of itself. This serum contains its biomimetic hydra complex – 16 minerals, amino acids and vitamins – as well as a super-hydrating combo of glycerin, glacial water and hyaluronic and polyglutamic acids.
You’ll also find niacinamide, oat ceramides and vitamin B5 in the ingredients list, which all support barrier function, as well as calming bisabolol and horse chestnut. It’s like a week of eating healthy for your skin in one dose.
Buy now £78.00, Cultbeauty.co.uk
The Inkey List polyglutamic acid serum
Best for: Budget
The Inkey List is a relatively new disruptor brand that offers ingredients-focused formulations at affordable prices. Its polyglutamic acid serum is the only product we could find that puts PGA front and centre. While other serums contain PGA with other ingredients, this is a great way to isolate its effects. It’s a thick, clear serum with great slip that immediately relieves dryness and tightness, and leaves skin soft and silky. A great base for make-up.
Buy now £12.99, Boots.com
Zelens z-melatonin night repair serum
Best for: Dull skin
Melatonin may be the hormone that helps regulate your sleeping and waking cycle, but applied topically it has been shown to help your body neutralise free radicals and to support the cells that produce collagen and elastin. As well as this ingredient, Zelens’s serum also contains peptide and ceramide complexes, hydrating hyaluronic and polyglutamic acids, niacinamide for clearness and evenness, and a polyhydroxy acid – gluconolactone – for texture, among other things.
It’s an ingredient list that justifies the price. The formulation is light and absorbs beautifully, leaving behind a soft glow, and skin is brighter, smoother and better rested by morning.
Buy now £165.00, Zelens.com
Decorte moisture liposome eye cream
Best for: Tired, irritated eyes
This jewel-like little pot contains a light, gel eye cream that’s cooling and relieving on first application; we love it on tired irritated eyes. It uses liposomes, which aren’t an ingredient but rather a delivery system that are tiny lipid sacs that hold ingredients while they penetrate the skin and then release them after the liposome is absorbed. The ingredient list features, of course, glycerin and hyaluronic and polyglutamic acids, for a soft, comfortable and hydrated eye area.
Buy now £59.00, Decortecosmetics.co.uk
Omorovicza midnight renewal
Best for: Mature skin
This, from the Hungarian skincare brand, contains retinal – not a typo, but a vitamin A derivative that requires only one conversion to retinoic acid, meaning it works incredibly quickly on the skin. Also on the ingredients list are bakuchiol, a gentle retinol alternative that helps stimulate collagen production and reduce fine lines, glycerin, hyaluronic acid, jojoba oil and polyglutamic acid. Its sunshine yellow formula spreads thinly and easily, leaving behind a light tackiness, and skin is baby-soft to the touch come morning.
Buy now £140.00, Lookfantastic.com
Glow Recipe watermelon glow ultra-fine mist
Best for: Midday refresh
We’ve long been sceptical about the use of mists in skincare, as so much product is dispensed into the air rather than directly on to your skin. But we’ve come to love this for a light, refreshing dose of moisture, whether on bare skin or over the top of make-up to refresh it during the day. It has a very fine spray and a mouth-watering watermelon scent, due to the huge concentration of watermelon in the ingredients (84 per cent, top spot in the list), as well as hyaluronic and polyglutamic acids, glycerin, amino acids and pumpkin seed oil.
Buy now £25.00, Cultbeauty.co.uk
Charlotte Tilbury magic serum
Best for: Irritation and redness
Contained in this dressing table-worthy bottle are what the brand calls “Charlotte’s magic 8” – a blend of eight peptides, vitamins, aloe vera, hyaluronic acid and flower oils and extracts – plus a brilliant trio of ingredients: vitamin C for clearer, brighter skin; niacinamide to help with even tone and improve the appearance of pores; and, of course, polyglutamic acid. It’s a fairly thin, milky serum that spreads easily and evenly and absorbs leaving no tackiness. Over time, we saw a good reduction in redness and irritation.
Buy now £60.00, Charlottetilbury.com
Kate Somerville dermalquench wrinkle warrior
Best for: Fine lines
This uses an unusual foaming delivery system so the product immediately feels light and airy on skin. Three different sized molecules of hyaluronic acid combine to offer penetration at different levels of the skin, along with brightening oxygen and, of course, polyglutamic acid. It gives a bright, fresh, plumped-up look to the skin and the appearance of fine lines is reduced. Although on first application it does have a slight shaving-foam smell, this fades quickly.
Buy now £85.00, Spacenk.com
The verdict: Polyglutamic acid products
If your skin is dry, dehydrated and feeling papery again a few hours after you’ve applied your skincare, Oskia’s isotonic hydra-serum is the best thing you can do for it. For an affordable way to try polyglutamic acid, and a clear way to isolate its effects, The Inkey List’s PGA serum delivers hydration and a plump, smooth base for make-up.
For glowy skin, we’ve also found the best hyaluronic acid serums and creams for hydration