The real reasons we layer skincare from thinnest to thickest products

We are all at different stages of our skincare journey, and we all use varieties of products for specific skincare goals. At some point, I am sure most of us learned that we should layer skincare products from thinnest to thickest somewhere online (a random blog, Instagram post, etc.) or from a friend. But have you ever wondered why that is the case? It makes logical sense when you think about it, but it is also interesting to learn the real reason why.

Myths around layering skin:

We will start by addressing current myths around the reasons why we layer our skincare products from thinnest to thickest. While researching this topic, I found numerous content online giving reasons like ‘thicker products have large molecule sizes and will block products with smaller molecules from penetrating the skin properly, which is why they should be applied last’. Though thicker products do indeed have larger molecular sizes than watery products, there are spaces between these molecules therefore, the claim about their sizes being the reason we layer the way we do is somewhat false.

So, what is the REAL reason for layering from thinnest to thickest?

The real reason is simpler than you think! It is about the order in which you apply products with high water content and those with higher oil content. We all know oil and water repel each other and never mix, so you can imagine what happens when you apply a product with more oil above the product with more water content.

For example, a toner has more water compared to serums (in fact, most toners do not even contain oil). Therefore, if you apply a serum with high oil content before toning your skin, the oil will obstruct water in the toner from absorbing into the skin properly, thereby hindering the skin from hydrating. The above reason is why we layer skincare the way we do.

(Illustration credit: Lab Muffin Blog)

In conclusion…

After learning this new and interesting fact about skincare layering, my curiosity got the best of me once again and I began to question ‘since facial oils are thinner than moisturizers & creams, which goes last?’. The answer is facial oil! I know this might be a little bit confusing for some people but, it shouldn’t be.
Facial oils have the highest oil content among skincare products, which makes them the heaviest product in our skincare routine (even if they feel thinner), therefore applying them last makes sense since they only trap moisture already in the skin & does not hydrate the skin.

To summarize, we apply watery products below because water hydrates, and oil does not since oil and water do not mix. I hope this article provided valuable information and answers regarding why we do certain things in skincare.