The Chemistry of Your Skin: Products You Shouldn’t Mix

You may already have your beauty routine set in stone, slapping on all your typical products before bed without a second thought. Though you may think that your applying products that are good for your skin or will cure your acne problems, you may be doing more damage than you think depending upon which products you combine in your routine.

It’s easy to forget the chemistry of your skin. Your skin’s pH balance is always shifting when you add products to it, and when it’s thrown off just enough you’re more prone to breakouts and irritation. Active ingredients in products can be harsh, so it’s important to take note of the chemicals you are applying to your skin.

VALLEY’s here to explain a few commonly used skincare products that should not combined to avoid irritation and breakouts.

Vitamin C and Chemical Exfoliants

Vitamin C is frequently applied in serum form to the skin for its brightening and anti-aging properties, which chemical exfoliants such as BHAs and AHAs  help breakdown the dead skin cells to help resurface the skin.

The issue here is with your skin’s pH balance. Vitamin C is very low on the pH scale, making it very effective on the skin. But when combined with the BHAs and AHAs in chemical exfoliants, the balance gets thrown off and it “effects the effectiveness” of the vitamin C, basically cancelling it out. Using one product in the morning and one at night avoids this “cancelling out” process, saving you money in the long run as well.

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Acne Treatments and Chemical Exfoliants

Both acne treatments (such as benzoyl peroxide) and chemical exfoliants can be very irritating to your skin. This irritation, such as redness or stinging, is a result of the pH levels in your skin being thrown off.

These products should be used on different days, and this will also help your skin build up the tolerance it needs to be able to fully absorb the ingredients in both products.

Hyaluronic Acid and Facial Oils

These two actually can be used together, but the order in which they are applied is key. When applying skincare products, a good rule of thumb is apply products from light to heavy consistency. More watery products should be applied first to allow them to soak into the skin, such as toners, followed by serums, creams and finally oils.

Hyaluronic acid, which is frequently found in super hydrating moisturizers, should always be applied before your facial oils. When oils are applied first they tend to stay on top of the skin, blocking it from absorbing any products you apply on top of it. This also may lead to clogged pores, causing you to breakout.

Benzoyl Peroxide and Retinol

Both of these products are heavy chemicals that can do amazing things to your skin. Benzoyl peroxide is an acne-combatting staple, killing any bacteria that had caused you to breakout. Retinol is used for eliminating scarring and anti-aging, working to remove the top layer of skin to make way for new cell growth.

The key here is to make sure you don’t use these products on the same day. Both have super active ingredients, and when paired together they can over-strip your skin and cause irritation and quite possibly breakouts. Try and alternate the two products on an every-other-day basis.


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