How to Use Salicylic Acid and Niacinamide in Your Skincare Routine for Clear, Matte Skin and Smaller-Looking Pores
One is a beta-hydroxy acid (BHA), and the other is a form of vitamin B3. Together, they’re especially helpful for oily skin, enlarged pores and adult acne. But even if you don’t deal with those conditions, they actually offer a long list of benefits for every skin type.
However, figuring out where these ingredients go in your skincare routine can be confusing. Can you apply them at the same time, or even in the same product? Will one inactivate the other? And in what order should you layer them?
I’ll be answering all of those questions and more in this tutorial. You will learn what salicylic acid and niacinamide can do for your skin, how to use them in your routine the right way, and the best products that I recommend trying.
What Does Salicylic Acid Do for Your Skin?
Salicylic acid is a chemical exfoliant and the most well-known BHA or beta-hydroxy acid. The BHA family also includes betaine salicylate and willow bark extract, which are gentler alternatives.
Here’s what salicylic acid and other BHAs do for your skin:
- Deep-cleans pores: The key difference between alpha- and beta-hydroxy acids is that BHAs are oil-soluble. That means salicylic acid is able to penetrate deep into pores to exfoliate their lining, remove excess oil and loosen clogged sebum.
- Prevents future acne: By keeping the pores clean and free of oil and dead skin cells, it acts as a comedolytic agent, preventing the comedones that lead to breakouts from forming.
- Exfoliates and smooths: Above the surface, it causes skin cells to shed off by dissolving intercellular cement, a.k.a. the “glue” that holds them together. This improves your skin’s overall texture and smoothness.
- Minimizes pore size: There are two ways that salicylic acid “shrinks” pores. Like all acid exfoliants, it creates a smoother look and feel to the skin surface that can give the illusion of decreased pore sizes. In addition, its ability to deep-clean the pores helps them to look smaller because they aren’t being stretched out by debris.
- Controls excess oil: It has been shown to decrease oily skin in acne sufferers, and also suppresses sebum-secreting cells from producing excess oil.
- Reduces inflammation and bacteria: Even at low concentrations, salicylic acid is bacteriostatic (prevents bacterial growth), and it has a mild anti-inflammatory effect.
- Fades post-acne marks and pigmentation: It can safely treat post-acne marks (both red and brown), even in darker skin tones, as well as hyperpigmentation, melasma and photodamage.
- Firms the skin: At higher concentrations, it can even thicken the epidermis (the uppermost layer of skin) and increase the density of collagen and elastin fibers for firmer, younger-looking skin.
What Does Niacinamide Do for Your Skin?
Niacinamide is a form of vitamin B3, a water-soluble vitamin that plays an important role in restoring cellular energy and helping cells to carry out their functions.
Here’s what niacinamide does for your skin:
- Controls excess oil: As little as 2% has been shown to reduce the amount and rate of sebum excreted.
- Reduces acne: For mild to moderate acne, one study found that 4% niacinamide is as effective as 1% clindamycin (a topical antibiotic) at reducing the amount and severity of lesions, without causing bacterial resistance. Another study found that 5% niacinamide is as effective as 2% clindamycin, with no side effects.
- Smooths skin texture: Both 4% and 5% concentrations produce significant improvements in skin texture. (Some researchers theorize that it does so by speeding up epidermal turnover, similar to a mild exfoliant.)
- Minimizes pore size: Niacinamide significantly reduces pore size and pore count, likely by reducing surface sebum.
- Reduces dryness: It alleviates dry skin by reducing transepidermal water loss (TEWL).
- Strengthens the skin barrier: It also thickens the skin barrier and increases levels of ceramides and free fatty acids, which improves its function and ability to hold onto hydration.
- Evens skin tone and fades pigmentation: As little as 4% niacinamide can significantly improve skin tone evenness and hyperpigmentation in just six weeks.
- Reduces redness and sallowness: It reduces red, blotchy skin (even rosacea) as well as yellowing (sallowness).
- Reduces wrinkles: Multiple studies have demonstrated that niacinamide produces significant improvements in fine lines and wrinkles, likely because it stimulates new collagen synthesis.
Should You Use Both Salicylic Acid and Niacinamide?
While salicylic acid and niacinamide are each effective on their own, there are synergistic benefits from using both in one routine.
If you’re only using salicylic acid, then you won’t get the barrier-strengthening support of niacinamide. Since it is a chemical exfoliant, salicylic acid can make your skin feel drier, especially when you’re first starting treatment. (That said, it is still far less irritating than glycolic acid, due to its higher molecular weight.) Adding niacinamide to your routine can help to counteract any side effects from the acid by increasing your skin’s ability to retain moisture, supporting barrier function and reducing redness.
On the flip side, if you’re only using niacinamide, then your pores won’t get the deep-cleaning that salicylic acid can provide. While niacinamide has shown positive results for mild to moderate acne, it plays more of a supporting role by reducing oil. It can’t remove dead skin cells or dislodge clogged sebum like salicylic acid can. Adding salicylic acid to your routine will do more to clear existing breakouts and prevent future acne.
As you’ve probably noticed, there’s also an overlap in what these two ingredients can do. They control excess oil, smooth the skin texture, minimize pores and fade discolourations. But they work through different pathways—so by using both, you can target these issues in two different ways for the best possible results.
Can You Mix Salicylic Acid and Niacinamide?
Mixing salicylic acid and niacinamide together, or layering one ingredient on top of the other at the same time, is a no-no. Here’s why.
Decreased Absorption of Salicylic Acid
In order to penetrate the skin and work as it should, salicylic acid is formulated with an acidic pH, typically between 3.0 and 4.0. A study comparing salicylic acid at various pH levels (pH 2.0, 5.0 and 7.0) found that the higher the pH, the less the skin absorbs.
In contrast, niacinamide is formulated with a neutral pH, usually around 6.0. So if you mix salicylic acid and niacinamide together, the niacinamide can raise the pH level of the acid, making it less acidic. That means less salicylic acid will be able to get into your skin, so it won’t be as effective.
The “Niacin Flush”
Mixing salicylic acid and niacinamide can also affect the performance of your niacinamide. Like I said, it normally has a neutral pH, but acidic conditions can trigger its conversion into niacin, another form of vitamin B3.
Niacin is notorious for producing the “niacin flush”—an episode of hot, red, flushed skin due the release of prostaglandin D2. If you’ve ever taken an oral niacin supplement, you’ve no doubt experienced it, but it can also happen when you use salicylic acid and niacinamide at the same time.
Fortunately, it’s only temporary, but when this happened to me, it lasted a couple hours (and there’s no way I could have covered it up with makeup!). I suspect this may be why some people believe that they are having a “reaction” to salicylic acid, niacinamide or both. It could simply be from applying them too close together in your routine.