In the world of skincare, there are many terms like “active” and “inactive ingredients.” If you’re new to skincare, you might find these words confusing. It’s completely normal; I struggled to understand the concepts too.

 But don’t worry because after many years of skincare experience, I now fully understand them and I’m ready to share that knowledge with you. In this article, you will clearly understand the difference between active and inactive ingredients, their respective roles, and why they both matter in skincare.

What are active ingredients in skincare and what do they do?

In the U.S., active ingredients are those regulated and recognized by the FDA (Food and Drug Administration). They are the key ingredients that target specific skin concerns and are scientifically proven to change the skin. As board-certified dermatologist Dr. Emily Newsom, M.D. explains, “An active ingredient has been proven in a lab by research to change the skin in some way; it’s an ingredient that has data behind it.”¹ For example, if a product claims to treat acne, then the active ingredient would be the one fighting against acne.

Categories of active ingredients

The long list of active ingredients can be divided into different categories. Here are some of the most popular categories and their ingredients listed for your reference:

1. Exfoliants

Function: Remove dead skin cells and improve skin texture
Example:

• Alpha-hydroxy acids (AHAs): Reduce fine lines, wrinkles, irregular pigmentation, and age spots.
• Beta hydroxy acids (BHAs): Deeply exfoliate the skin, treat acne and oil production, and improve texture and color in sun-damaged skin.

2. Moisturizers and Hydrators

Function: Attract and retain moisture in the skin
Example:

• Hyaluronic Acid: A powerful humectant that hydrates, has anti-aging benefits, and aids in faster wound healing and scar reduction.
• Lactic acid: An AHA that exfoliates and acts as a humectant, retaining moisture in the skin.

3. Antioxidants

Function: Protect the skin from free radicals and environmental damage
Example:

• Vitamin C (L-ascorbic acid): Brightens the skin, stimulates collagen production, and is beneficial for sun-damaged skin.
• Niacinamide (Vitamin B3): Improves skin elasticity, enhances the skin barrier function, and protects against melanoma.

4. Anti-Aging Ingredients

Function: Boost collagen production, reduce fine lines, wrinkles, and slow the aging process
Example:

• Retinoids: Derived from vitamin A, minimize fine lines, wrinkles, and acne scars, and improve skin tone and texture.
• Peptides: Short chains of amino acids that signal the skin to produce more collagen.

5.Acne Treatment

Function: Treat and prevent acne
Example:

• Benzoyl Peroxide: Kills acne-causing bacteria and clears pores.
• Salicylic acid: Deeply exfoliates and unclogs pores.

While active ingredients can be very effective for your skin and may make your skin thank you for them, they can also cause irritation, redness, or dryness if used incorrectly. Like me, when I started using them, I thought that using more would be better than using less. Therefore, I started using products with high concentrations of active ingredients. As a result, it caused irritation and redness on my skin.

 So it’s important to start slowly when using an active ingredient, especially if your skin is not used to them. Begin with a small amount and increase gradually to understand how your skin reacts. Additionally, using sunscreen is very important, especially when using active ingredients, because the active ingredient treats your concerns and in the process can make your skin more sensitive.

What are inactive ingredients and what do they do?

In the U.S., inactive ingredients are those not classified and regulated as actives by the FDA. While they don’t directly address specific skin concerns like active ingredients do, they play a vital and supporting role in skincare formulations. This doesn’t mean that their not importance. Many inactive ingredients are excellent moisturizers and contribute to the overall efficacy of skincare products. Inactive ingredients mainly focus on enhancing product texture, stability, and absorption, ultimately supporting the effectiveness of active ingredients.

Categories of inactive ingredients

The list of inactive ingredients in skincare is quite extensive. Here are some of the most popular categories and their ingredients listed for your reference:

1. Fragrances and Colorants

Function: Enhance the sensory experience of the product (note: fragrance can sometimes be a skin irritant)
Examples: Fragrance oils, dyes, pigments

2. pH Adjusters

Function: Adjust the pH of the formulation for skin compatibility and stability of active ingredients
Examples: Citric acid, sodium hydroxide

3. Preservatives

Function: Prevent microbial growth and extend the shelf life of the product
Examples: Ascorbic acid, vitamin E, salt, phenols, oil extracts

4. Emollients

Function: Soften and moisturize the skin
Examples: Shea butter, cocoa butter, silicones

Inactive ingredients can cause skin reactions, especially if you have sensitive skin or allergies. Common culprits include fragrances, preservatives, and certain types of alcohols. Always conduct a patch test when trying new products.

Can an ingredient be both active and inactive?

No, an ingredient cannot be both active and inactive. However, many ingredients can function as both depending on their concentration and the purpose of the formulation in a product. Let’s clarify using glycerin as an example in skincare formulations:

Active Ingredient: Glycerin can be considered an active ingredient in products where its primary role is to hydrate and moisturize the skin. These formulations often use glycerin at higher concentrations and in specific formulas designed for moisturizing benefits.

Inactive Ingredient: In other formulations, glycerin serves as an inactive ingredient. Here, it acts as a humectant that stabilizes the product, improves texture, and enhances spreadability. While glycerin still provides moisturizing benefits, it is not the primary active ingredient in these products. In these types of formulations, glycerin is often used at lower concentrations.

Difference between active and inactive ingredients in skincare

The key difference between active and inactive ingredients lies in their purpose. Active ingredients target specific concerns and steal the spotlight in skincare products, delivering direct results. In contrast, inactive ingredients do not target specific concerns; instead, they enhance the overall quality of a product.

If you’re still finding it hard to understand the concept of active and inactive ingredients, think of them like the lead actor and the supporting cast in a movie. Active ingredients take the spotlight, delivering direct results like the star of the show. Meanwhile, inactive ingredients play a crucial role behind the scenes, enhancing the performance of the active ingredients, similar to how supporting actors enhance the lead’s performance.

Now that you understand the difference between active and inactive ingredients, let’s address whether we need both.

Do we need both?

The simple answer is yes. Different skin types have different needs, but all skin types require both active and inactive ingredients for healthy skin. They complement each other’s strengths and weaknesses. Active ingredients provide potent, specific, and immediate results, while inactive ingredients act as the foundation of a product, enhancing the effectiveness of active ingredients, maintaining results over time, and fulfilling general skincare needs. Using only active ingredients can lead to dryness, irritation, sensitivity, etc., and active ingredients are less effective without the support of inactive ingredients. Conversely, using only inactive ingredients will not give you the result you want.

So, the next time you’re purchasing a skincare product, take a moment to ensure it contains both active and inactive ingredients because they are both essential for maintaining healthy skin.

How to determine active and inactive ingredients in skincare products?