Peter Thomas Roth Peptide 21 Wrinkle Resist Serum Versus Peter Thomas Roth Even Smoother Glycolic Retinol Resurfacing Serum
Updated on February 06, 2025
Overview
What they are
These products are both reef safe serums. They have a total of 13 ingredients in common
Cool Features
They both contain exfoliants, hyaluronic acid, retinoid, Vitamin C and Vitamin E
Suited For
They're both likely to be good for fighting acne, 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 common allergens, fragrances or parabens
We independently verify ingredients, and our claims are backed by peer-reviewed research. Spot a product that needs an update? Let us know.
Ingredient Info
Peter Thomas Roth Peptide 21 Wrinkle Resist Serum 56 ingredients
Peter Thomas Roth Even Smoother Glycolic Retinol Resurfacing Serum 47 ingredients
About this product
About this product
At a glance
Click on any of the items below to learn more
Peter Thomas Roth Peptide 21 Wrinkle Resist Serum 56 ingredients
Peter Thomas Roth Even Smoother Glycolic Retinol Resurfacing Serum 47 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.
Water. 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 WaterSqualane is an emollient that helps the skin hold onto moisture. It's an oily liquid that occurs naturally in certain types of fish and plant oils.
Because squalane boosts hydration in the skin, it also comes with plenty of benefits: it is an antioxidant and can help fight free radicals and skin damage. Squalane is also found to have a detoxifying effect when applied.
Squalane comes from squalene, which occurs naturally within the sebum of our skin. It is one of the oils our skin produces to keep itself hydrated. Squalane is the hydrogenated version of squalene and has a longer shelf life.
Research shows that squalane is non-irritating (even at 100% concentration).
In general, it's a fantastic ingredient. It does a great job at hydrating the skin, and it's suitable for those with sensitive skin.
The source of squalane may impact malassezia / fungal acne. This is because olive oil derived squalane can contain impurities such as fatty acids and plant waxes. Sugarcane derived squalane is recommended for anyone with malassezia concerns.
Is squalane vegan?
This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.
Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.
Read more about squalene with an "e".
Learn more about SqualaneSodium Hyaluronate is hyaluronic acid's salt form. It is commonly derived from the sodium salt of hyaluronic acid.
Like hyaluronic acid, it is great at holding water and acts as a humectant. This makes it a great skin hydrating ingredient.
Sodium Hyaluronate is naturally occurring in our bodies and is mostly found in eye fluid and joints.
These are some other common types of Hyaluronic Acid:
Learn more about Sodium HyaluronateAscorbic 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 AcidLecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of mixture of phospholipids.
This ingredient has emollient and emulsifying properties.
As an emollient, lecithen helps soften the skin and creates a barrier to keep moisture in.
As an emulsifier, it also helps prevent water and oil ingredients from separating. Lecithin can also help ingredients be better absorbed by the skin.
This is because the phospholipids in lecithin produce liposomes. Liposomes help other ingredients get through the skin barrier.
Depending on the source of this ingredient, lecithin may not be fungal acne safe. This is because some sources of lecithin come from soybean oil, which may feed the malassezia yeast that feeds fungal acne.
We recommend reaching out to the brand you are purchasing from to inquire about the source of their lecithin.
Learn more about LecithinPolysorbate 20 is made by combining ethoxylation of sorbitan, ethylene oxide, and lauric acid. It is a mild cleansing agent, surfactant, and emulsifier.
As a surfactant, it helps collect dirt and oils for washing. Emulsifiers prevent oils and water from separating.
Polysorbate 20 also adds scent to a product. Since it is made using sorbitol, it has a sweet scent. Sorbitol can also be found in fruits such as apples and peaches.
The lauric acid used to create Polysorbate 20 is often derived from coconuts.
Polysorbate 20 may not be fungal acne safe.
Learn more about Polysorbate 20Leuconostoc/Radish Root Ferment Filtrate is a natural preservative. It comes from fermenting radish roots with a bacteria called leuconostoc.
Leuconostoc comes from lactic acid.
This ingredient has antimicrobial properties and helps prevent the growth of bacteria in a product.
Leuconostoc is used to make the traditional Korean side-dish, kimchi. It is also used to make sourdough bread (both incredibly yummy foods).
Learn more about Leuconostoc/Radish Root Ferment FiltrateXanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.
On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.
Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.
Learn more about Xanthan GumSilica is a mineral naturally found in our skin. It helps to thicken and smooth the texture of a product. It also acts as an agent for other ingredients by increasing the absorption of other ingredients into the skin.
Silica is often used for absorption and can help reduce shine when products are applied. Silica occurs in naturally in materials like clay and sandstone, and it can also be produced synthetically.
Silica is present naturally within the skin during collagen production and when reducing inflammation.
Learn more about SilicaSodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.
In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.
Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.
"Alkaline" refers to a high pH level. A low pH level would be considered acidic.
Learn more about Sodium HydroxidePotassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.
This ingredient comes from potassium salt derived from sorbic acid. Sorbic acid is a natural antibiotic and effective against fungus.
Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.
You'll often find this ingredient used with other preservatives.
Learn more about Potassium SorbateSodium Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.
Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.
Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.
It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.
Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.
We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.
Learn more about Sodium BenzoatePhenoxyethanol 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.
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