How to Use Niacinamide and an AHA or BHA in Your Skincare Routine for Smooth, Clear, Even-Toned Skin

Before you layer these ingredients, read this!
Niacinamide and glycolic acid salicylic acid

Ever since I shared my tutorial on the benefits of niacinamide, I've been asked how to use it with my OTHER favourite skincare ingredient: acid!

Take a look at this question:

If you've been wondering about this, too, this tutorial is for you! I'll cover:

  • The benefits of using niacinamide and lactic acid, glycolic acid or salicylic acid 
  • The problem with getting them from a single product
  • The problem with mixing them together
  • The three best ways to use them in your routine for maximum results!

Why Use Niacinamide and Acids

Niacinamide and glycolic acid salicylic acid

Both niacinamide and acids can help improve skin texture, pigmentation, dryness, dullness, wrinkles and acne.

First, let's review the reasons WHY you'd want to include these two ingredients in your skincare routine.

Niacinamide (Vitamin B3):

Alpha- and beta-hydroxy acids (AHAs and BHAs):

The Problem with Getting Niacinamide and Acid from a Single Product

Niacinamide and glycolic acid salicylic acid

Tarte Knockout Tingling Treatment, COSRX AHA 7 Whitehead Power Liquid and COSRX BHA Blackhead Power Liquid all contain both acid and niacinamide.

So, if you want niacinamide AND acid in your skincare routine, why not use a single product that includes both?

Well, it's a matter of concentration. 

To REALLY get the benefits of niacinamide, you're going to need a product with at least four or five percent, because that's the amount used in most of the clinical studies. 

For example, four percent niacinamide was proven to reduce pigmentation, fine lines and wrinkles and acne. Five percent was found to improve redness and sallowness.

Is the two percent that COSRX uses enough to do anything? (Apparently, ALL of their products with niacinamide contain a two percent concentration.)

Maybe. There are a few studies that saw two percent helped with pigmentation, oily skin and increasing hydration. If those are the only things you're looking to treat, then you might be fine with this low amount. But no, you won't be getting all of the potential benefits. 

Still want to go with a single product? Here are the best AHA and BHA treatments that also have niacinamide in their ingredients lists. (Note that COSRX is the only brand that is transparent about the exact concentration.) 

The Problem with Mixing Niacinamide and Acid Together

Niacinamide and glycolic acid salicylic acid

Niacinamide treatments from Glossier, Paula's Choice, SkinCeuticals, Skin Inc Supplement Bar and The Ordinary.

Alright, so you've decided that you want to use two separate products in order to get a higher concentration of niacinamide. 

Your best bets for high-dose niacinamide are:

Now, what happens if you mix niacinamide with your AHA or BHA of choice, or layer one straight on top of the other?

One thing it's going to do is make your acid less effective. 

The Skincare Edit Recommends

Acids typically have a pH between 3.0 and 4.0, while niacinamide is around 5.0 to 7.0. When you mix them together, the niacinamide will raise the pH of the acid. 

This study compared the absorption of AHAs at pH 3.0 and 7.0, and found that the higher the pH, the less the skin absorbs. That means you'd be missing out on all the benefits your acid has to offer.

Another problem with mixing niacinamide and acid is that it can cause redness and flushing. That's from the acid lowering the pH of the niacinamide, which triggers a conversion into niacin (another form of vitamin B3). 

If you've ever taken a high-dose niacin supplement, then you may have experienced the infamous "niacin flush." This is what it looks like:

Niacin flush

The red, blotchy skin associated with a niacin flush. (Photo: @mynutrishcoach)

Imagine the same thing, concentrated on your face! I've tested this out myself, and it's no joke. Makeup can't even cover it up! 

While it is temporary and harmless, who wants to have to wait a couple hours for their crazy red skin to go away? Nobody!

The Solution: How to Apply Niacinamide and Acid in Your Skincare Routine

Niacinamide and glycolic acid salicylic acid

Avoid mixing acid exfoliants (such as these from COSRX and Kate Somerville) with niacinamide-based treatments (such as these from Skin Inc Supplement Bar and Glossier).

To avoid the flushing issue and to get the most out of your products, you've got three options.

Option 1: Apply Them at Different Times of Day

An easy way to use both niacinamide and acid is to apply them at different times of day.

If your mornings are typically rushed, it's often most convenient to use niacinamide in the morning and acid at night. This is because niacinamide is non-acidic, so it can be applied underneath your hydrating serum, moisturizer, oil or sunscreen without having to wait in between layers. 

Acids, on the other hand, need to be separated from higher-pH products by about 30 minutes, to allow them time to work at their optimal pH. So, you may prefer to apply acid at night, when you have more time to wait in between steps (if you are using any other products on top of it).

That said, you can definitely reverse this and do acid in the morning and niacinamide at night, if you've got more time. Just make sure that you are wearing a good high-protection sunscreen (30 minutes after the acid) and avoiding prolonged direct sun exposure. AHAs in particular have been shown to make the skin more photosensitive and vulnerable to sun damage (whereas BHAs actually have some photoprotective effects).

Option 2: Apply Them on Alternate Mornings or Nights

Another option is to apply your niacinamide and acid on alternate mornings or nights. 

So, one night you could apply your niacinamide after cleansing. The next night, you could use your acid. Or this could happen in the mornings, if you prefer.

Again, the one caveat here is that if you are using additional products on top of them, you need to be mindful of pH levels. My general rule is that any products that are more than about 1.0 apart need to be separated by a waiting period.

Option 3: Apply Them 30 Minutes Apart

Your last alternative is to use your niacinamide and acid at the same time, just 30 minutes apart. That way, each product is able to work at its intended pH. You can do this once or even twice a day, depending on your skin type.

When layering products, you always want to be moving in order of lowest to highest pH. So start with the acid, straight after cleansing, since it's going to be around pH 3.0 to 4.0. 

Incorporating a 30-minute wait will give your skin pH a chance to return to normal, about pH 5.5. Then you can apply your niacinamide, which will be around pH 5.0 to 7.0, without having to worry about the niacin conversion. After that, proceed with your hydrators and SPF.


Niacinamide and glycolic acid salicylic acid

Niacinamide and acids can both fit in your skincare routine, as long as you use them at the right time, in the right order.

If you've ever wondered whether you can incorporate niacinamide and acid in one skincare routine, rest assured—you definitely can!

While there are a few acid treatments out there that also give you a low dose of niacinamide (like the COSRX AHA and BHA), I do recommend using separate products if you want to see the best results.

Personally, I've noticed brighter skin, faded pigmentation and fewer breakouts from using either The Ordinary or Paula's Choice 10 percent niacinamide serums in addition to my favourite acid, the COSRX BHA. But if you prefer a different niacinamide or acid, that's totally up to you!

The key is to make sure you use them at the right time, in the right order, to keep their pH levels intact (and to avoid the dreaded red flush!).

I hope this tutorial helps you determine how to make the most of these ingredients in your routine. I'd love to hear about your results!

Shop Editor’s Picks

Do you use niacinamide or acids?
Have you tried them both in one routine?

Read Next

Skincare routine - fall 2017

How to Do My Fall Skincare Routine

What I'm using to fade pigmentation, prevent breakouts and ward off aging.