Hyaluronic acid is one ingredient that is everywhere — every single moisturizer, every serum, and even every sheet mask. Most brands advertise it as a miracle hydrator that works for everyone, and I fell for that lie for way too long.
So what does it really do? It is actually a humectant, meaning it pulls water towards it. Your body already produces hyaluronic acid. It is naturally in your skin, sitting between cells and holding moisture. When you apply it topically, it can bind 1,000 times its weight in water, which is incredible. And, by the way, that water needs to come from somewhere first.
In humid conditions, it collects moisture from the air and pulls it into your skin. But in dry conditions — like in a heated room, or an air-conditioned room anyways — it can pull moisture from the lower layers of your skin and let it evaporate. So that means that everyone thinks it is so moisturizing, actually thinks it is pulling moisture from your skin.
I really only learned this when I moved to a more dry climate. I started to feel tight and flaky skin when I used all the products I loved. I was in a low humidity apartment and layering serums with hyaluronic acid and wondering why my skin felt so bad.
The hype gets molecular weight wrong also. Not all hyaluronic acids work the same. High molecular weight HA only sits on the surface and makes a film to hold the moisture there. Low molecular weight HA can go a little deeper. Most serums don’t say which type they’re using, or they only use one size, which affects how the serum feels and performs. Most product pages don’t have the info, but the best formulas use several different molecular weights.
Then there is concentration. It’s all hype when brands just say ‘WITH HYALURONIC ACID’. They fail to say how much is actually in there. Some research says that 1–2% is enough to be effective, but there are many products that contain much less than that and still advertise it as a key ingredient. You’re just paying for a load of filler.
If you live in a cooler place, or are careful when it comes to layering it under an occlusive moisturizer that seals it in, hyaluronic acid can feel great. It is gentle. It is just hydration and isn’t active like the ones I talked about before — salicylic or glycolic acids — so it won’t exfoliate or irritate.
Using it over something heavier could even make your skin more dry, and that’s especially the case if you apply to dry skin. It works best damp skin because it helps bind with the product.
As such, I’ve changed how I used it to apply right after washing my face while still wet, then apply a heavy moisturizer or squalane oil. That’s when the product is supposed to give results like plumping and the bouncy feeling. I had that initially, but it was because I put the product before going to bed to dry skin, let it sit, and I was wondering why my face felt like it was being constricted.
Mixing it with actives works fine too. I use it with niacinamide, and before retinol, and it’s only ever been neutral to that. It’s a good ingredient to use in a routine as long as you use it correctly.
If you want to give it a shot, The Ordinary’s Hyaluronic Acid 2% + B5 is about 8 dollars and they use several molecular weights, which is uncommon at this price point. Or if you want something a bit more elegant, the Vichy Minéral 89 feels less sticky and sits nicely under makeup, and is about 30 dollars.
Just don’t get your hopes up for the product to work miracles on its own. And for the love of god, put something over it.
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