Can You Use Niacinamide with Vitamin C?

Can you use niacinamide with vitamin C? Yes, it’s safe to use these two ingredients together, despite the outdated study claiming that the combination can cause a reaction. Some influencers still say to keep the two apart, even though that study isn’t actually accurate to the way skincare works today. Layered correctly, the two of them together without any problems and help your skin look more even and brighter. Let’s do a deep dive into the details so you can see for yourself how it works.

Where the “Don’t Mix Them” Myth Came From 

First, let’s talk about where the myth comes from. Why was it considered unsafe to mix niacinamide and vitamin C for skincare?

That advice traces back to a 1960s study, which combined niacinamide and vitamin C at very high temperatures, with very concentrated solutions and long exposure times. Under those conditions, the mixture of niacinamide and vitamin C turned yellow, with the niacinamide breaking down to niacin. Niacin causes irritation and flushing, unlike niacinamide which is safe.

It was because of this study that skincare experts warned consumers not to mix the two ingredients. But in fact, the study is really inaccurate to the way skincare works. Modern skincare formulas don’t use concentrated solutions and are never exposed to high temperatures. It takes very high heat to break niacinamide down to niacin. Today, niacinamide and vitamin C are considered safe to use together, provided they are layered properly. Side effects like flushing are very rare with modern skincare.

Why Niacinamide and Vitamin C Work Well Together 

Skincare addicts love vitamin C because it brightens your skin and protects against aging. Because it helps the skin with collagen production, vitamin C can also help your skin look firmer and smoother.

Meanwhile, niacinamide helps support your skin’s barrier and even out your skin tone and color. The pair of niacinamide and vitamin C gives you the benefits of both, so you have brighter, more even skin.

For more information about niacinamide, see our complete guide to the benefits of niacinamide for acne.

Does pH Matter When Layering Them? 

Aside from the old inaccurate study, there’s another concern about using vitamin C and niacinamide together, which is that each ingredient likes a different pH. Vitamin C (L-ascorbic acid) works best with an acidic pH and niacinamide prefers a more neutral pH. Seeing that, some people are like, ok, those two don’t go together.

But in real life, it doesn’t really matter if each ingredient needs a different pH. Your skin adjusts, and modern formulas are in any case built to be layered. So this doesn’t affect the effectiveness of pairing niacinamide and vitamin C.

How to Use Niacinamide with Vitamin C 

Now let’s discuss how to practically layer these ingredients for maximum effectiveness.

The Right Order

First thing to pay attention to is the order of application. Apply vitamin C first, wait 2-3 minutes, and only then apply niacinamide. Then, move on to the moisturizer and sunscreen part of your skincare routine.

When to Apply

You can either apply vitamin C and then niacinamide every morning, or split up the application by doing vitamin C in your morning routine and niacinamide at night. Niacinamide works well at night to replenish the skin barrier, while vitamin C does its brightening work in the morning before you go out.

Using a Combined Product

Another effective application option is to use a product that has already combined the two ingredients for you. Look for a formula that has niacinamide at about 2% to 5% concentration for maximum benefits. 

Tips to Avoid Irritation 

Although vitamin C and niacinamide won’t usually cause any side effects even when combined, the following tips can help avoid any irritation when you start the routine.

• Patch test the combination on one area of your face skin before you do your full face.
• Start out with one ingredient, then add the other one a week or two later.
• Start the vitamin C a few times a week instead of every day if you’re new to it.

Using Niacinamide and Vitamin C with Other Actives

If you also want to use retinol, in addition to the vitamin C and niacinamide, you’ll need more spacing built into your routine. A good option is to use vitamin C in the morning, and retinol and niacinamide in the evening.

If you’re using exfoliating acids like AHAs or BHAs, don’t use them on the same day. Do vitamin C one day, and exfoliating acids a different day.

For more information on retinol and niacinamide, check out our complete guide to pairing niacinamide with retinol.

Frequently Asked Questions 

Which goes first, niacinamide or vitamin C?

Vitamin C goes first. Apply it, wait 2 to 3 minutes, then apply niacinamide. Vitamin C works best on clean skin, and the short wait lets it settle before the next layer. 

Do I have to use vitamin C in the morning?

No, but morning is the best time. Vitamin C is an antioxidant, so it adds a layer of defense under your sunscreen. If your skin prefers it at night, that works too. Just keep it away from retinol and exfoliating acids on the same night. 

Can sensitive skin handle both niacinamide and vitamin C?

Usually, yes. Start with a lower-strength vitamin C or a gentler form, such as magnesium ascorbyl phosphate. Patch test first and add one product at a time. Use vitamin C a few times a week until your skin adjusts. Niacinamide tends to be well tolerated and can help calm the skin. 

What if my vitamin C serum turns orange or brown? 

That means it has oxidized. Light, air, and heat break vitamin C down, and the serum loses potency as it darkens. A pale yellow tint is normal. Deep orange or brown, or a metallic smell, means it’s time to replace it. To slow oxidation, keep the bottle tightly closed and store it in a cool, dark place. An opaque or dark glass bottle helps, and so does a drawer instead of a sunny bathroom shelf. Many serums last about three months after opening, so check the label. 

Shop Niacinamide and Vitamin C Products

Now that you’ve seen that mixing niacinamide and vitamin C is safe for most skin types, plus you’ve explored the proper routines for applying them, shop the products that will make it easy for you to implement the skincare routine effectively. Here’s to brighter, more even skin every day!