Oxidation: What is it and how can you minimise it?

Have you ever put a complexion product on your skin and thought you had found your foundation shade, only for it to slowly become much darker or more orange? This process is called oxidation and is the same as when you see an apple turn brown once you’ve bitten into it.

In scientific terms, this process is defined by the loss of electrons to the oxygen in the air. Despite electrons being invisible to the naked eye, this process causes the degradation of the atoms in your foundation leading to the colour change. Common foundation ingredients, like iron oxides, are notoriously known for contributing to oxidation.

So, is there anything you can do to minimise the situation?

You may be surprised to know it is not just oxygen that can cause oxidation – your foundation can also react with the natural oils in your skin! The best way to minimise this reaction is to use a primer which will form a barrier between your skin and your foundation. Primers, like the Nars Pore & Shine Control Primer, also help to give your makeup longevity, so regardless of oxidation it is a great product to add to your makeup routine.

As products age, oxidation becomes more and more apparent. I am sure we are all guilty of using makeup beyond its expiry date, but did you know that the older a product is the more dramatically it oxidises? Eventually, the product will oxidise while still in its original packaging! We recommend making a note of the date you first use your foundation bottles to keep an eye on the expiration date.

Another thing to be aware of when trying to minimise oxidation is that water-based formulas are more likely to oxidise due to the fact that H2O is harder to stabilise when compared with other foundation bases (like silicone). That being said, you don’t need to avoid water-based foundations, just simply be aware when finding your match that oxidation is an important consideration. Here at Match My Makeup, our matches are determined after a period of oxidation has occurred in order for you to be able to find your most accurate match!

Using a setting powder, like the Laura Mercier Translucent Powder, is another way of minimising oxidation – it not only provides a barrier between your foundation and the oxygen in the air, but also minimises oil build up on your face. While oils commonly used in foundations are more stable than H2O, it can still react with the oils in your skin so using blotting paper before you apply foundation and setting powder after you apply the foundation will help to mitigate this colour change.

While oxidation can be annoying and embarrassing when it catches you unaware, there are many ways to minimise it. Taking oxidation into account when finding your foundation shade, prepping and finishing your skin and base correctly and keeping an eye on the expiration dates of your products can all help to avoid the dreaded orange appearance of oxidised foundation.