Skincare Products you Should Never Mix

Do you feel that you are not getting the results you hoped for from your skincare products? This could be the case if you mix the wrong ingredients together or you do not follow the correct order of layering skincare products ingredients. Knowing what products mix well together when layered together is a clever way of getting the maximum benefits from your skincare products. On the other hand, layering ingredients that do not mix well together can cause skin irritation or increased sensitivity to the skin. Dr Adil Sarwar from Skin Science Clinic London put together a list of skincare ingredients that you should never mix together in order to get your skincare ingredients to work in your favour.


Retinoids (Retinol) are the go-to anti-aging skincare ingredients. Retinol works by enhancing skin cell turnover and stimulating collagen production. But the body cannot produce collagen without having enough Vitamin C. This would make anyone think that Retinol and Vitamin C go hand in hand.

However, since they are both very active, potent ingredients, layering these two products together as part of the same skincare routine, is a recipe for skin irritation, increased skin sensitivity and redness. Moreover, l-ascorbic acid (Vitamin C) is most effective in an acidic, low pH environment, while retinoids are delivering the best results in a more alkaline environment. So, by using both ingredients simultaneously you will actually minimise the powerful benefits each ingredient can have for your skin if used separately.

With this being said, we do encourage you do integrate both ingredients in your skincare routine, just at different times of the day. Retinoids are best to be applied during your night-time routine. While retinol will help you fight those fine line efficiently, it can make your skin more photosensitive, which can increase the risk of sun damage to the skin. SKIN65 recommends using Vitamin C during the day, in combination with a SPF50, although 30 is acceptable. Given its unmatched ability to protect your skin from free radicals, Vitamin C thrives during the daytime when combined with a high SPF sunscreen. Using these two powerful active ingredients at different times of the day will help you get the maximum anti-aging benefits for your skin.


Thankfully, social media definitely helped increase the popularity of Niacinamide. The benefits niacinamide brings for the skin makes it an all-around must-have ingredient that, frankly, should be part of any skincare routine. It helps soothe the skin, even the skin texture, brighten the skin, balance oil production, calm inflammation and tighten pores.

While it is a very potent ingredient, try not to layer Niacinamide with Vitamin C together, as part of the same skin care routine. Most Vitamin C products on the market are formulated with l-ascorbic acid, which does wonders for your skin. However, l-ascorbic acid is a very unstable molecule which can easily become less effective when layered with certain ingredients, such as niacinamide. The science behind this is that Vitamin C performs best at a low pH, while niacinamide works better at a higher pH. As a result, you can layer the two ingredients together, but you will not get the maximum benefits from both of these products because the Vitamin C will not perform as well as if it was used on its own.

SKIN 65 recommends using niacinamide in your evening routine and Vitamin C in your morning routine. One of our favourite niacinamide serums is the Skinceuticals Discoloration Defense Serum . With 5% Niacinamide, this will really transform your skin. While it works wonders for treating hyperpigmentation or melasma, it is suitable for all skin types. The Skinceuticals Metacell Renewell B3 is formulated with 5% niacinamide as well. It comes as an emulsion rather than a serum and really focuses on delivering additional hydration to the skin by maintaining the levels of hyaluronic acid and skin firmness. For acne-prone skin, I also recommend the La Roche-Posay Effaclar Serum which combines 2% niacinamide with salicylic and glycolic acids to really address clogged pores and support the natural skin renewal.


AHAs (like glycolic acid) and Retinoids are both derivatives from Vitamin A. They are both used to combat aging because each of them promotes skin cell turnover and increase collagen production. One may think that using two powerful ingredients in their anti-aging skincare routine will deliver better, quicker results. Unfortunately, this couldn’t be further from the truth. In this case, less is more.

While not an exfoliant like AHAs and BHAs, Retinol is a peeling agent, given its ability to stimulate cell turnover by getting rid of the old, damaged skin cells. As a result, combining Retinoids with acids can cause skin irritation, increased skin sensitivity, higher risk of sun damage, and leave your skin overly dry by attacking your skin’s moisture barrier. It is important that you do not use Retinoids and AHA/BHAs in the same day. You will see much better results if you use AHA/BHAs and Retinol on alternate days of the week. So, when you are exfoliating using AHA/BHAs based products, skin the Retinol step in your skincare routine for the evening. As each of these ingredients can leave your skin relatively dry, don’t forget to add hyaluronic acid in your routine to replenish your skin’s moisture and lock it in.

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