Here’s all you need to know about lactic acid in skincare

Photo: Ming Xi / Instagram

In the last two installments of our weekly acid guide we touched base on two of the most popular acids in skincare: Hyaluronic acid and salicylic acid. We’ve likely already heard of them — and might even be using them in our skincare regimens now.

When it comes to acid in skincare though, there’s a huge array that we may not have heard of. Ones that are less commonly known, but still effective skincare ingredients. This week, we’re all about lactic acid.


What is lactic acid?

Here’s all you need to know about lactic acid in skincare

Photo: First Aid Beauty / Instagram

It’s a natural acid derived from milk, fruit and plants. It’s also naturally produced by our body. Commonly known as the gentler cousin to glycolic acid, lactic acid has a larger molecular compound that doesn’t penetrate our skin’s deeper layers. This means it’s not going to be as irritating on the skin as glycolic acid (read about it next week).


What does lactic acid do for our skin?

Here’s all you need to know about lactic acid in skincare

Photo: First Aid Beauty / Instagram

Primarily, lactic acid sloughs off dead skin cells on our skin to even out uneven complexions. It’s an alpha-hydroxyl-acid (AHA), which means it works on the skin’s surface to “dissolve”  the dead and dull layer.

It’s different from a facial scrub because scrubs (manual exfoliation) tugs and pulls at the skin, forcibly scrubbing away superficial dry skin patches. So your skin may feel smooth after, but it’s not necessarily clean. Stubborn debris and dead skin cells that are “glued” between the epidermal cells can’t be rolled away with a physical exfoliator; they have to be dissolved with lactic acid.

Lactic acid also helps increase cellular turnover. That means it’s a stimulant and accelerant when it comes to our skin’s collagen production. Lactic acid is also used to plump up fine lines and wrinkles for a more youthful appearance.


Things to note when using lactic acid

Here’s all you need to know about lactic acid in skincare

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Chemical exfoliants expose fresh new skin to the sun more than usual (because our dead skin tends to “shield” the newer skin). This applies to all acids — but especially ones like lactic acids whose primary role is to exfoliate the skin. And that means wearing broad spectrum sunscreen out after every lactic acid treatment is crucial; your skin is fragile and needs time to build up its resistance towards UV rays.

Skins react to acids differently. A lactic acid serum may be a little too harsh for someone with sensitive skin, but may not show results on someone with “hardier” skin. If the product irritates your skin, step away from it. If the product is not showing results after three to four weeks, it’s time to change it up. Remember, it may not always be the percentage of acid in a product that matters; its formula matters too.

Some experts agree that AHAs in skincare products show instant results. Skin will feel more refreshed and smoother to the touch. A slight tingling sensation might take place as the acid gets to work, but should disappear in a couple of seconds.


Some of our favourite products with lactic acid:


Will you use lactic acid in your skincare regimen?