COSRX The 6 Peptide Skin Booster Serum Versus Nature Republic The First Peptide Boosting Serum
Updated on June 28, 2024
Overview
What they are
These products are both reef safe serums. They have a total of 24 ingredients in common
Cool Features
They both contain hyaluronic acid, niacinamide, peptides and Vitamin E
Suited For
They're both likely to be good for fighting acne, anti aging, dry skin, brightening skin, sensitive skin, oily skin, reducing pores, scar healing, dark spots and better texture
Free From
They both do not contain any common allergens, parabens, silicones or sulfates
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
COSRX The 6 Peptide Skin Booster Serum 44 ingredients
Nature Republic The First Peptide Boosting Serum 58 ingredients
About this product
About this product
At a glance
Click on any of the items below to learn more
COSRX The 6 Peptide Skin Booster Serum 44 ingredients
Nature Republic The First Peptide Boosting Serum 58 ingredients
Key Ingredients
Benefits
Concerns
Key Ingredients
Benefits
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 WaterDipropylene Glycol is a synthetically created stabilizer and solvent. It is a part of the glycol class in the alcohol family.
Dipropylene Glycol helps dissolve and evenly distribute ingredients. It also helps decrease viscosity and thin out texture.
As a masking agent, Dipropylene Glycol can be used to cover the smell of other ingredients. However, it does not have a scent.
Studies show Dipropylene Glycol is considered safe to use in skincare.
Learn more about Dipropylene GlycolGlycerin 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 Glycerin1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.
It is a:
- Humectant, drawing moisture into the skin
- Emollient, helping to soften skin
- Solvent, dispersing and stabilizing formulas
- Preservative booster, enhancing the antimicrobial activity of other preservatives
Niacinamide has emerged as an all-star ingredient due to its many benefits.
It is known to treat acne by reducing inflammation. It also helps fade dark-spots and strengthen the skin by promoting the growth of the ceramide barrier.
Other benefits include smoothing wrinkles and minimizing redness.
The cherry on top? Niacinamide can also help build keratin, a protein that keeps skin firm.
When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.
Niacinamide can be mixed with other ingredients to boost benefits. For instance, it has shown to be effective when used with copper, folic acid, and zinc to treat acne.
Learn more about NiacinamideAcetyl Hexapeptide-8 is a peptide. A common name for this peptide is Argireline.
Argireline has a similar function to botox; it prevents muscle movement and contractions slightly. By preventing muscles from moving, argireline also prohibits the formation of fine lines and wrinkles. However, research is lacking in proving this ingredient to be as effective as botox.
On the other hand, argireline 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 Acetyl Hexapeptide-8Copper Tripeptide-1 is a peptide naturally found in body fluids. Peptides are building blocks for protein.
Studies show this ingredient tells our body to create more collagen and elastin. Collagen is a protein that makes connective tissue. Elastin is the protein responsible for giving our skin elasticity. Our bodies start to slow down collagen and elastin production with age.
Boosting collagen and elastin production can help create a healthier skin barrier. Having a healthy skin barrier means having firm and hydrated skin. It's a win-win situation!
This ingredient helps with scar healing. This is because it breaks down damaged collagen, the main component of scar tissue. It may also help with reducing sunspots, acne scars, and uneven skin tone.
On top of all this, Copper Tripeptide-1 is also an antioxidant. Antioxidants help the body fight off free-radicals. Free radicals are molecules that damage our cells, such as pollution and tobacco smoke.
More benefits: Copper Tripeptide-1 helps maintain tissues in blood vessels and promote natural hyaluronic acid in skin.
Read more about other common types of peptides here:
Learn more about Copper Tripeptide-1This small molecule peptide has similar benefits to Argireline, the "botox" peptide.
According to the manufacturer, this peptide mimics snake venom to freeze muscles. This prevents muscle movement and contractions to prohibit the formation of fine lines and wrinkles.
While this seems promising, research is lacking in proving this ingredient to be as effective as botox.
Learn more about Dipeptide Diaminobutyroyl Benzylamide DiacetateThis synthetic peptide is created from palmitic acid, arginine, histidine, and phenylalanine.
According to the manufacturer, this peptide is great at soothing skin inflammation.
Allantoin plays a role in soothing and moisturizing the skin. Because of this, it is often added to products with strong active ingredients.
Some studies have shown this ingredient can promote wound healing with higher concentrations.
Allantoin is derived from the comfrey plant but produced synthetically for cosmetic products to ensure purity.
Learn more about AllantoinSodium 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 HyaluronateSerine is an amino acid naturally found in our body. Our bodies use amino acids to create protein.
Amino-acids help give keep our skin hydrated. They play an important role in the skin barrier, which keeps the skin plump and firm.
Serine is a non-essential amino acid, meaning we don't need to obtain it from eating foods.
Learn more about SerineAlanine is an amino acid and is already found in the human body. Our skin uses alanine to build collagen, elastin, and keratin.
This ingredient is an amino acid that helps build proteins and moisturizes skin. It is already present in our skin as our bodies produce them naturally.
Glycine already plays a role in helping keep our skin moisturized as amino acids transport moisture throughout our skin.
As collagen is made up of glycine and other amino acids, it is believed glycine may help our skin produce more collagen.
Learn more about GlycineThreonine is an amino-acid. It helps hydrate the skin and has antioxidant benefits.
Our skin uses threonine for creating collagen and elastin. Humans are not able to create threonine and must get it through eating foods such as fish, lentils, poultry, sesame seeds, and more.
Arginine is an amino acid that is important for human development. Your body uses is it to produce hair keratin and skin collagen.
As a cosmetic ingredient, Arginine has antioxidant properties and can also help repair damaged skin. This ingredient is derived either synthetically or from animals.
Arginine isn't fungal acne safe when used in the presence of other lipids (fats, fatty acids, oils, esters, etc). Oils and fats occur naturally within the skin, so take caution when using Arginine if you're prone to fungal acne.
Learn more about ArginineProline is an amino-acid. It helps moisturize the skin and plays an important role in creating proteins.
Our skin uses proline as one of the building blocks for producing collagen.
In medicine, proline is used as an osmoprotectant. This means it helps prevent oxidative degradation in other drugs.
Our bodies are able to produce proline naturally, but certain conditions may inhibit this production. In that case, proline can be obtained from eating egg whites, soy protein, dairy products, asparagus, mushrooms, and seaweed.
Learn more about ProlineBetaine is a common humectant (a substance that promotes retention of moisture). It's known to be gentle on the skin and can help balance hydration.
This ingredient is best for improving hydration and soothing irritated skin. Studies also show it helps even out skin tone.
Fun fact: Betaine is naturally created in the skin and body. The kind found within cosmetic products can be either plant-derived or synthetic.
Learn more about BetaineGlutamic Acid is an amino acid that is found in all living organisms. Our bodies use this to help nerve cells in the brain communicate with other cells.
In cosmetics, glutamic acid is a famous humectant. It draws water from the air to your skin, keeping your skin hydrated (like hyaluronic acid).
An in-vitro study from 2024 found glutamic acid to play a role in inhibiting inflammation and thus a potential skin-soothing ingredient.
Other studies show it to be have potential wound healing, skin barrier repair, and hair growth properties.
Glutamic acid has poor solubility in water and other solvents.
Learn more about Glutamic AcidTocopherol (also known as Vitamin E) is a common antioxidant used to help protect the skin from free-radicals and strengthen the skin barrier. It's also fat soluble - this means our skin is great at absorbing it.
Vitamin E also helps keep your natural skin lipids healthy. Your lipid skin barrier naturally consists of lipids, ceramides, and fatty acids. Vitamin E offers extra protection for your skin’s lipid barrier, keeping your skin healthy and nourished.
Another benefit is a bit of UV protection. Vitamin E helps reduce the damage caused by UVB rays. (It should not replace your sunscreen). Combining it with Vitamin C can decrease sunburned cells and hyperpigmentation after UV exposure.
You might have noticed Vitamin E + C often paired together. This is because it is great at stabilizing Vitamin C. Using the two together helps increase the effectiveness of both ingredients.
There are often claims that Vitamin E can reduce/prevent scarring, but these claims haven't been confirmed by scientific research.
Learn more about TocopherolDextran is a sugar (polysaccharide) with skin hydrating properties.
Fun fact: Louis Pasteur first discovered this ingredient as a microbial product in wine.
Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
- It is a solvent, meaning that it helps to dissolve other ingredients. This also enhances the absorption of the product into one's skin.
- It is a humectant, which means that it helps attract moisture into the skin.
- It helps improve product application.
- It has mild preservative properties.
Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
Ethylhexylglycerin (we can't pronounce this either) is commonly used as a preservative and skin softener. It is derived from glyceryl.
You might see Ethylhexylglycerin often paired with other preservatives such as phenoxyethanol. Ethylhexylglycerin has been found to increase the effectiveness of these other preservatives.
Adenosine is in every living organism. It is one of four components in nucleic acids that helps store our DNA.
Adenosine has many benefits when used. These benefits include hydrating the skin, smoothing skin, and reducing wrinkles. Once applied, adenosine increases collagen production. It also helps with improving firmness and tissue repair.
Studies have found adenosine may also help with wound healing.
In skincare products, Adenosine is usually derived from yeast.
Learn more about AdenosineIngredient Ratings
Here's what our community thinks of the ingredients in these products.
When to use
COSRX The 6 Peptide Skin Booster Serum 44 ingredients
Nature Republic The First Peptide Boosting Serum 58 ingredients

Reviews
Here's what our community thinks
COSRX The 6 Peptide Skin Booster Serum 44 ingredients
I was breaking out for 3 months and had no idea what was going on. Then my mom mentioned she’s getting small bumps around her jawline from another peptide serum (Skin1004) and it clicked. Stopped using it week ago and didn’t get a single pimple.
Didn’t see any positive results.
No difference seen so far as i started last week, goes on nice and absorbs fast, no scent whatsoever and pretty hydrating
EDIT: GAVE ME CLOSED COMONDONES LIKE THE OTHER REVIEWER. DONT USE.