The Science of Polyglutamic Acid: Is It Better Than Hyaluronic Acid?

Ingredient Science
This single ingredient holds 4x its weight in water, but does it dethrone the hydration king?
Expert Analysis · Honest Reviews · Real Results
1.🧪The Hydration Heist

Hyaluronic Acid is the queen of hydration. But there’s a new molecule in town trying to steal the crown.

Polyglutamic Acid (PGA) is a peptide that can hold four times its weight in water. HA can hold one thousand times. The math is weird, but the hype is real.

2.💧The Contender

This is The Inkey List’s Polyglutamic Acid Serum. $16.99. The claim? A “moisture barrier” effect that outlasts HA.

1

The Texture

A clear, slightly goopy gel — thicker than their HA serum.

2

The Feel

Leaves a distinct, slightly tacky film. Not a ghost.

3

The Price

Under $20. You’re paying for the single ingredient science.

a woman holding a bottle of medicine and a magnifying glass

Photo: Content Pixie / Unsplash

3.🔬Ingredient Intel

The hero is 3% Polyglutamic Acid. It’s a humectant, but it’s also supposed to form a breathable film on top of skin to lock water in.

It’s not a solo act. They added 1% Hyaluronic Acid. A backup singer, not the lead.

  • Polyglutamic Acid (3%): Forms a hydrating film on skin
  • Hyaluronic Acid (1%): Adds a layer of water-binding
  • Squalane: A light, non-greasy emollient
  • Betaine: A hydrator that protects skin stress
4.📊Skin Feel Test

Applies like a slick gel. That tacky finish is immediate — you feel it for a good 10 minutes. It’s not unpleasant, just… present.

After two weeks, my skin felt consistently cushioned. The surprise? It played nicer over dry patches than HA, which can sometimes pull water from skin if the air is dry.

💡

One Thing: Apply to damp skin, then immediately seal it with a moisturizer. The tackiness disappears.
5.🤔The Real Deal

My foundation went on smoother — no cakey patches. But it’s not a dewy glow. It’s more like a hydrated, matte cushion. Pore appearance? Zero change.

Buy if
You have dry or dehydrated skin and want a moisture buffer under makeup.
⏭️

Skip if
You hate any hint of texture or tackiness in a serum.
💰

Worth it?
Yes, as a targeted hydrating layer. But it’s a supplement, not a replacement.
6.Final Call

It doesn’t dethrone HA. It’s its strategic partner. PGA is the sealant, HA is the magnet. Together, they’re a powerhouse.

7.5/10
A smart, affordable hydrating booster.
🛍️

Where to Buy: Sephora or directly from their site. At this price, just get the full size.