What Does Foundation Oxidizing Mean? How Do You Know It’s Happening?

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Have you looked in the mirror mid-way through the day, only to realize that’s not how your foundation looked when you put it on?

No one wants to look like they’re still using an old-school self-tanner from the 80s. So what happened? That change in color, usually to the orangey side, and change in texture could be from oxidation of your foundation.

What does foundation oxidizing mean, exactly? What are the signs of oxidation?

Foundation oxidation occurs when the color and/or consistency of your foundation changes.

In this article, we are going to explore the question: what does it mean when your foundation oxidizes? We will take a look at the oxidation process, how you can tell if your foundation has oxidized, and how to help prevent foundation oxidation.

We’ll also look at some foundation products that market themselves to be oxidation-free.


What is Oxidation?


Chemically, in the simplest of terms, oxidation is a process in which an electron is removed from a molecule during a chemical reaction.

The oxidation process is not limited to foundation, or to makeup. It happens every day, all around us.

When you cut an apple or a pear and leave it out, it will turn brown. That’s oxidation.

Rust is a form of oxidation.

The Statue of liberty, most notable for her iconic green color, wasn’t always green. The statue of liberty is covered in copper plates.

When the statue was erected, it was a dull brown.

Over the next 30 years, it slowly changed to the green color it is today, and that we all now associate it with. The change in color of the Statue of Liberty is also a result of oxidation.

So what does this have to do with foundation?

What Does It Mean When Your Foundation Oxidizes?

NYX Foundation

Technically speaking, oxidation is caused by a chemical reaction when an ingredient in your foundation comes into contact with oxygen. The oxygen molecule steals an electron from the molecules in the foundation, which causes it to degrade.

In basic terms, oxidation in a foundation can result in changes in color and consistency.

How Do You Know If Your Foundation is Oxidized?

The longer you keep a foundation, the more likely it will oxidize. Over time the oxidation affects the color of the foundation in the bottle.

After six months to a year, you will probably notice a distinct color change in your foundation from the time that you bought it.

It may even start to separate.

If you see this happening, it’s definitely time to toss it and buy a new one.

The thing is that foundation may have oxidized long before it starts to change color in the bottle. Your biggest clue that your foundation has oxidized is if you apply it in the morning and it’s the right shade, but later it starts looking brassy, orange, or flat as the day goes on.


Causes of Foundation Oxidation

1. Exposure to Air

If you’ve had your foundation for longer than six months, you may see a change in the foundation color and texture in the bottle. It may even start to separate. This type of oxidation is caused by your foundation being exposed to oxygen after repeatedly opening and closing the bottle.

At some point, most foundations will oxidize if you’ve had the bottle for too long.

This is why cosmetics have an expiry date.

But oxidation can start well before you notice any physical difference in the product before you put it on. The air is not the only thing your foundation may be reacting to.

2. Cosmetic Products

Another possible culprit of changes in the appearance of your foundation could be as a result of other cosmetic products you are using on your face, like the moisturizer you’ve applied underneath your foundation.

Try different moisturizers to make sure it’s not a reaction between the ingredients in your moisturizer and the foundation that’s causing the problem.

3. Natural Oils

Your foundation may also be reacting to the natural oils in your skin. Be sure that the foundation you are using is formulated for your skin type.

4. Your Facial Care Regime

Are you properly prepping your face by making sure it’s clean and free of excess oil and dirt? Are you using too many products? Both of these can play a role in how foundation wears throughout the day.

This is why it’s super important to know your skin type and understand what it needs. This way, you’ll make sure the products you are using are beneficial for your skin.

Overcleaning and stripping away all of your skin’s natural oils will cause your skin to react by producing more oi. This can change the appearance of your foundation.

Using too many heavy creams and serums can block pores and cause the skin to become congested. This too can affect how the foundation looks after you’ve put it on.

That all having been said, a change in color and/or texture of your foundation after you’ve applied it might not necessarily be oxidation. There is something you need to consider before you ditch your foundation:

5. The Lighting

Check first of all that it’s not just the light! Indoor lighting (particularly fluorescent) can be deceptive, not to mention unflattering. Vampires. Everywhere.

Check your foundation in natural light both when you put it on in the morning and later on in the day.

This way you can make sure it’s not your bad vanity mirror lighting or office bathroom lighting that’s making it look different.

How do I Stop My Foundation From Oxidizing?

Finding the perfect foundation is hard enough. But then, finally finding the right foundation, you realize that it doesn’t look good halfway through the day. It is frustrating, to say the least!

Oxidation is a common problem with the foundation, but we have a few tips to help prevent oxidation and extend the shelf life of your foundation.

Check the ingredients

The minerals commonly found in foundation that are prone to oxidation are titanium dioxide, zinc oxide, and iron oxide.

If these minerals are high up in the ingredient list, then the makeup is more likely to oxidize. Titanium dioxide is very commonly used as a white pigment, so lighter foundations will have higher levels of it.

Foundation stabilized with antioxidants is much less likely to oxidize. And unless you’ve been living under a rock, you’ve most certainly at least heard of antioxidants.

Antioxidants protect cells from the damage caused by “free radicals”. Free radicals are an unstable byproduct of the process of oxidation during normal metabolism.

Regular body processes, like breathing and digestion, produce free radicals.

Try to find foundations high in antioxidants like No Makeup Foundation  or 100% PURE 2nd Skin Foundation .

Common antioxidants found in foundations include vitamin E, green tea, and resveratrol.

Use a Foundation Primer

A foundation primer puts a barrier between the skin and your foundation, making it less likely for reactions between the oils in your skin and the foundation.

Keep the Lid On Tight

Make sure your foundation is always tightly capped when not in use.

What Foundations Do Not Oxidize?

Foundation oxidation is a common enough problem that there are specially formulated foundations to address this issue.

We’ve put together a full article on our favorite foundations that do not oxidize.

Here’s a quick list:

Estée Lauder Double Wear Stay-in-Place Foundation 3W1 Tawny
Estée Lauder Double Wear Stay-in-Place Foundation 3W1 Tawny
Won't change color, smudge or come off on clothes. Feels lightweight and comfortable.; For a look that lasts all day, without touchups.
$43.99 Amazon Prime
All Day Luminous Weightless Foundation - # 4 Deauville/Light by NARS for Women - 1 oz Foundation
All Day Luminous Weightless Foundation - # 4 Deauville/Light by NARS for Women - 1 oz Foundation
provides physical barrier against the sun and pollution; Satin finish. Skin Tone: Light; more luminous & healthy looking
$35.00 Amazon Prime
Cover FX Natural Finish Foundation - N25, 1 fl. oz.
Cover FX Natural Finish Foundation - N25, 1 fl. oz.
Available in global shades; oil free foundation has a silky; vitamin C and vitamin E to protect against free radicals


We hope we’ve answered the question – what does it mean when a foundation oxidizes? 

Here’s a recap… 

You can help to prevent your foundation from oxidizing by: 

  • maintaining a skin care regime suited to your particular skin type
  • making sure your foundation is tightly capped 
  • Ensuring you don’t keep your foundation past its expiration date. 

Your other option is to opt for a foundation that does not oxidize, like the ones we’ve listed above.

See also:

Written by Kayla Young

Kayla is the founder of LuxeLuminous. She has worked professionally in the tanning industry for years. She has been interested in esthetics since childhood, and has tried every hair, skin, and makeup product ever produced (more or less).