Updated on May 26, 2025
Overview
What they are
These products are both reef safe serums. They have a total of 5 ingredients in common
Cool Features
They both contain AHA and Vitamin C
Suited For
They're both likely to be good for anti aging, dry skin, brightening skin, oily skin, reducing pores, scar healing, dark spots and better texture
Free From
They both do not contain any harsh alcohols, common allergens, fragrances, oils, parabens or silicones
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Ingredient Info
SkinCeuticals C + AHA 12 ingredients
ISDIN Flavo-C Serum 10 ingredients
What's inside (and what isn't)
What's inside (and what isn't)
At a glance
Click on any of the items below to learn more
SkinCeuticals C + AHA 12 ingredients
ISDIN Flavo-C Serum 10 ingredients
Key Ingredients
Benefits
Concerns
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
Ascorbic Acid is is pure Vitamin C. This form makes up the largest amount of vitamin C found naturally in our skin.
Not only is vitamin C great for your overall health and immune system, it also has plenty of benefits on your skin.
Vitamin C is best used for brightening skin. It improves dark spots, acne scars, and hyperpigmentation. This is because it blocks the process of skin darkening when exposed to UV.
Remember: Vitamin C should not replace sunscreen!
Your skin uses vitamin C to build collagen. Collagen is one key component in having a strong skin barrier and plump skin. Vitamin C also plays a role in regulating collagen, thus making it effective in improving wrinkles and fine lines.
Ascorbic acid shows potent antioxidant activity. As an antioxidant, it helps fight free-radicals. Free-radicals are molecules that may damage your skin cells. These antioxidants also protect skin against UV damage.
The best formulations include Vitamin E and/or ferulic acid. These two ingredients help stabilize and provide a boost in the benefits of ascorbic acid. This is because ascorbic acid becomes unstable when exposed to UV and air. In fact, you can tell your ascorbic acid has oxidized when it turns an orange-yellow color.
Ascorbic acid is generally compatible with other ingredients. However, using ascorbic acid with other active ingredients might cause irritation. Two ingredients: copper ions and benzoyl peroxide, will inactivate ascorbic acid completely.
Read more about other types of Vitamin C:
Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.
Learn more about Ascorbic AcidLactic Acid is an AHA that is derived from fermenting lactose, a carbohydrate from milk. It removes the top layer of old and dead skin cells and helps increase cell turnover.
Benefits of Lactic Acid are that it can help to reduce large pores and reduce the effects of aging. Some potential downsides are that it can be bad for dry skin, cause irritation, worsen eczema, and worsen rosacea.
Not only does it help exfoliate the skin, it helps strengthen the skin's barrier. When applied, lactic acid helps the skin create ceramides.
Lactic acid is an over-the-counter chemical exfoliant that comes from the fermentation of lactose — a carbohydrate found in milk.
Legend has it that Cleopatra used to bathe in sour milk to help reduce wrinkles.
Read more about some other popular AHA's here:
Learn more about Lactic AcidPhenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.
It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.
Propylene Glycol is an odorless, colorless liquid. As a humectant, it helps skin retain moisture. It also aids in delivering active ingredients.
Another role of this ingredient is preventing a product from melting or freezing. Propylene glycol also adds antimicrobrial properties to a product, elongating product lifespan.
This ingredient is considered an organic alcohol and commonly added into both cosmetics and foods.
Those with sensitive skin or conditions may develop a rash when using this ingredient.
Learn more about Propylene GlycolWater. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.
So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Stay hydrated!
Learn more about WaterIngredient Ratings
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