IT Cosmetics Bye Bye Lines Anti-Aging Serum Versus Peter Thomas Roth Peptide 21 Wrinkle Resist Serum
Updated on February 06, 2025
Overview
What they are
These products are both reef safe serums. They have a total of 12 ingredients in common
Cool Features
They both contain exfoliants, hyaluronic acid, peptides, 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 or parabens
What's Inside
They both contain silicones
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
IT Cosmetics Bye Bye Lines Anti-Aging Serum 112 ingredients
Peter Thomas Roth Peptide 21 Wrinkle Resist Serum 56 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
IT Cosmetics Bye Bye Lines Anti-Aging Serum 112 ingredients
Peter Thomas Roth Peptide 21 Wrinkle Resist Serum 56 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 WaterGlycerin is already naturally found in your skin. It helps moisturize and protect your skin.
A study from 2016 found glycerin to be more effective as a humectant than AHAs and hyaluronic acid.
As a humectant, it helps the skin stay hydrated by pulling moisture to your skin. The low molecular weight of glycerin allows it to pull moisture into the deeper layers of your skin.
Hydrated skin improves your skin barrier; Your skin barrier helps protect against irritants and bacteria.
Glycerin has also been found to have antimicrobial and antiviral properties. Due to these properties, glycerin is often used in wound and burn treatments.
In cosmetics, glycerin is usually derived from plants such as soybean or palm. However, it can also be sourced from animals, such as tallow or animal fat.
This ingredient is organic, colorless, odorless, and non-toxic.
Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
Learn more about GlycerinCaprylyl Glycol is a humectant and emollient, meaning it attracts and preserves moisture.
It is a common ingredient in many products, especially those designed to hydrate skin. The primary benefits are retaining moisture, skin softening, and promoting a healthy skin barrier.
Though Caprylyl Glycol is an alcohol derived from fatty acids, it is not the kind that can dry out skin.
This ingredient is also used as a preservative to extend the life of products. It has slight antimicrobial properties.
Learn more about Caprylyl GlycolButylene Glycol (or BG) is used within cosmetic products for a few different reasons:
Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.
Learn more about Butylene GlycolSqualane 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".
Is squalane an oil?
Squalane is often called an oil, but it’s technically not; it’s a hydrocarbon, meaning it’s only made of carbon and hydrogen, unlike true oils which are triglycerides made of fatty acids and glycerol.
The term “oil-free” isn’t regulated, so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.
While some people avoid oils thinking they cause breakouts, the right kind of oil (or oil-like ingredient like squalane) can actually help balance and hydrate your skin. It’s worth testing out simple oils or squalane to see what works best for your skin.
Learn more about SqualanePhenoxyethanol 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.
Potassium 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 BenzoateRetinyl palmitate is a form of retinoid. Retinoids are the superstar class of anti-aging ingredients that include tretinoin and retinol.
This particular ingredient has had a bumpy year with its rise and fall in popularity.
First, Retinyl palmitate is created from palmitic acid and retinol. It is a retinol ester and considered one of the weaker forms of retinoid.
This is because all retinoids have to be converted to Tretinoin, AKA retinoic acid. Retinyl Palmitate is pretty far down the line and has to go through multiple conversions before its effects are seen.
Due to this long and ineffective conversion line, the benefits of Retinyl Palmitate are debated.
Studies show Retinyl Palmitate to help:
Dermatologists say this ingredient is ineffective because it isn't used in high enough concentrations in cosmetics.
This ingredient used to be found in sunscreens to boost the efficacy of sunscreen filters.
The downfall of Retinyl Palmitate was due to released reports about the ingredient being correlated to sun damage and skin tumors.
While there is a study showing this ingredient to cause DNA damage when exposed to UV-A, there is no concrete proof of it being linked to skin cancer. It is safe to use when used correctly.
All retinoids increase your skin's sensitivity to the sun in the first few months of usage. Be especially careful with reapplying sunscreen when using any form of retinoid.
Currently, this ingredient is still allowed in cosmetics all over the world. In Canada, cosmetics must have a warning label stating the product to contain Retinyl Palmitate
Fun fact: This ingredient is often added to low-fat milk to increase the levels of Vitamin A.
Learn more about Retinyl PalmitatePalmitoyl Oligopeptide is a form of peptide. It is created by blending peptides with palmitic acid. Peptides are building blocks for protein.
Due to the palmitic acid base, it may not be malassezia folliculitis safe.
This ingredients tells our body to create more collagen. Collagen is a protein that makes connective tissue. Boosting collagen production leads to a healthier skin barrier. Having a healthy skin barrier means having firm and hydrated skin.
Read more about other common types of peptides here:
Learn more about Palmitoyl OligopeptideAscorbic 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 AcidPalmitoyl Tetrapeptide-7 is a peptide. Peptides are building blocks for protein.
This ingredient consists of four amino acids and palmitic acid. These amino acids are arginine, proline, glutamine, and glycine.
This ingredient has many benefits. These benefits include boosting collagen production, fighting inflammation, and reversing UV damage.
By preventing our bodies from producing interleukins, Palmitoyl Tetrapeptide-7 helps fight inflammation. An interleukin is a chemical that signals to the body to produce an inflammatory response. Interleukin production is accelerated by UV radiation.
Palmitoyl Tetrapeptide-7 tells our body to create more collagen. Collagen is a protein that makes connective tissue. Boosting collagen production leads to a healthier skin barrier. Having a healthy skin barrier means having firm and hydrated skin.
Read more about other common types of peptides here:
Learn more about Palmitoyl Tetrapeptide-7Ingredient Ratings
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