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Is this underrated acid actually a hydrating powerhouse?

Polyglutamic acid might not yet be part of your skincare lexicon – but, if you’re looking for something to help plump, hydrate and smooth skin, it's likely about to become your new go-to.

It isn’t as famous as hyaluronic, or half as hyped as vitamin C, but polyglutamic acid is the suits-everyone skin hydrator to unite us all. Here, the pros explain everything you need to know – including the polyglutamic acid skincare products that truly deliver.

‘Polyglutamic acid is a multifunctional biopolymer produced via fermentation of L-glutamic acid with bacteria,’ explains Dr. Marko Lens, founder of Zelens. In layman’s terms? It’s a peptide with excellent humectant properties, which means it attracts water from the surrounding environment and holds it within the skin.

As with most humectants, pretty much every skin type will get on well with polyglutamic acid – it’s a real crowd-pleaser. Dr. Lens describes it as especially well suited to ‘dry, dull, stressed and tired skin’. There are no contraindicating ingredients (meaning it won’t react negatively with any actives in your routine) and sensitive skin types can get involved with little risk.

So far, so familiar: and yes, polyglutamic acid does perform similarly to your go-to hyaluronic acid. However – plot twist – the former can actually hydrate skin even more effectively.

‘Polyglutamic acid is often compared with hyaluronic acid because they boast similar hydrating properties,' explains. Dr. Lens. 'However, what the majority of the people do not know is that polyglutamic acid can hold up to 5 times more moisture than hyaluronic acid – it's really an excellent humectant.’

Polyglutamic acid has a larger molecular weight than HA, meaning it sits closer to the surface of the skin. This might not sound like a good thing, but actually means your product will smooth the outermost layers of skin brilliantly, leading to results you can really see: think plumper, glowier skin and foundation that sits beautifully on top.

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So, why has hyaluronic been winning the popularity contest for so many years? Dr. Lens puts it down to marketing and familiarity. 'The use of hyaluronic acid has been much wider simply because people know that hyaluronic acid is present in our skin naturally – and also because it has been used widely as an (injectable) filler.' In fact, you don't need to choose between one or the other: many of our favourite products actually combine the two, to really double-down on the hydrating appeal.

Polyglutamic acid is relatively easy to formulate with, and so we're seeing it pop up in a wide array or products: think serums, face masks, creams and even some make-up. Below, see the ones team ELLE really rates.

This is the one to go for if you struggle to keep your redness-prone skin calm and clear. It's first and foremost a skin-soother, designed to tackle dryness and irritation, and works brilliantly on skin that's so dry it tends to flake. Team it with the matching moisturiser for serious improvements.

Studies have found topical melatonin to be an effective ingredient in protecting the skin from environmental threats: in short, it's an anti-inflammatory, antioxidant hero that skin loves. This creamy serum combines melatonin with polyglutamic acid to leave skin hydrated and shielded every morning. It's a great choice for mature or especially tired skin that needs an all-round pick-me-up.

While many hydrating serums offer ephemeral benefits, this one is designed specifically to impart moisture that really goes the distance. Massaged into damp skin and locked in with a layer of moisturiser, this blend of polyglutamic acid and biome-boosting fermented extracts really does keep skin supple from day to night.

This is simply a brilliant, no-nonsense serum that amps up hydration without overloading skin. Use it liberally, day and night - it plays especially well under make-up.

More than just a great hydrator, this hard-working essence (apply it after cleansing, as you would a serum) contains polyglutamic acid and niacinamide in a base of ferments, meaning it works especially well on oily, acne-prone skin. Expect a seriously dewy result after the first use.

For a serious skin reboot, consider investing in 111 Skin's intensive ampoule course, which rehydrates and rebalances skin in seven days. Each single-use vial contains a potent blend of humectants that sinks straight into skin, eliminating dehydration as quickly as possible.

Polyglutamic acid works well in make-up too – especially 'dewy' base products. This clever product blends a touch of brightening pigment with hydrating extracts to ensure skin both looks and feels supremely glowy. Mix a drop into your foundation, or simply wear it on top of SPF.

Decorté makes some excellent hydrating products, and this eye cream is a standout. It uses clever encapsulation technology to ensure the humectants inside are gradually released into the skin over time, ensuring hydration that sees you through the whole day.

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