Updated on October 25, 2023
Overview
What they are
These products are both reef safe . They have a total of 13 ingredients in common
Suited For
They're both likely to be good for dry skin
Free From
They both do not contain any parabens or sulfates
What's Inside
They both contain common allergens and fragrances
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
Kérastase Défense Thermique Heat Protecting Leave-In Treatment for Weakened Hair 37 ingredients
Olaplex Nº.9 Bond Protector Nourishing Hair Serum 30 ingredients
At a glance
Click on any of the items below to learn more
Kérastase Défense Thermique Heat Protecting Leave-In Treatment for Weakened Hair 37 ingredients
Olaplex Nº.9 Bond Protector Nourishing Hair Serum 30 ingredients
Notable Ingredients
This product contains 1 ingredient that may have this attribute:
This product contains 1 ingredient that may have this attribute:
Benefits
This product contains 2 ingredients that may have this attribute:
This product contains 1 ingredient that may have this attribute:
This product contains 1 ingredient that may have this attribute:
This product contains 2 ingredients that may have this attribute:
Concerns
This product contains 2 ingredients that may have this attribute:
This product contains 2 ingredients that may have this attribute:
This product contains 2 ingredients that may have this attribute:
This product contains 4 ingredients that may have this attribute:
This product contains 3 ingredients that may have this attribute:
This product contains 3 ingredients that may have this attribute:
Benefits
This product contains 1 ingredient that may have this attribute:
This product contains 1 ingredient that may have this attribute:
Concerns
This product contains 1 ingredient that may have this attribute:
This product contains 2 ingredients that may have this attribute:
Ingredients Side-by-side
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.
Oil 2 Concerns
Cocos Nucifera Oil is obtained from the kernels of the coconut fruit. In other words, this is coconut oil.
Phenoxyethanol 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.
Propylene Glycol Dicaprylate/Dicaprate is a mixture of Propylene Glycol Dicaprylate and Propylene Glycol Dicaprate.
Sodium 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.
This ingredient is created from dehydrating xylitol in acidic conditions. Xylitol is a famous sugar and humectant.
This ingredient is a preservative and often used for it's anti-static properties. You'll most likely see this ingredient in hair conditioners.
Limonene is a fragrance that adds scent and taste to a formulation.
Ethylhexylglycerin (we can't pronounce this either) is commonly used as a preservative and skin softener. It is derived from glyceryl.
Sorbitan Oleate is created from compounds in oleic acid and sorbitol. It is used to stabilize a product by preventing ingredients from separating.
2 Concerns
Linalool is a fragrance and helps add scent to products. It's derived from common plants such as cinnamon, mint, citrus, and lavender.
5 Concerns
Isopropyl Alcohol is more commonly known as rubbing alcohol. It is most commonly used as a solvent, meaning it helps other ingredients dissolve.
This ingredient is a preservative, antimicrobial, and emulsifier. It is often used in cosmetics for its ability to cleanse, condition, and reduce static.
Glycerin is already naturally found in your skin. It helps moisturize and protect your skin.
We don't have a description for Hydrolyzed Vegetable Protein Pg-Propyl Silanetriol.
EU Allergen
Benzyl Salicylate is a solvent and fragrance additive. It is an ester of benzyl alcohol and salicylic acid. This ingredient can be naturally found in some plants and plant extracts.
EU Allergen
Coumarins are a group of substances found naturally in plants. There are over 1300 types of coumarins identified. It has a natural vanilla scent.
EU Allergen
Citral is a fragrance and used to add a lemon-like scent to products. It is both naturally found in plants and created synthetically. In plants, it is commonly occurring in lemon myrtle, lemongrass, lemon tea-tree, lemon verbena, and other citruses.
Fragrance Preservative 6 Concerns
Benzyl Alcohol is most commonly used as a preservative. It also has a subtle, sweet smell. Small amounts of Benzyl Alcohol is not irritating and safe to use in skincare products. Most Benzyl Alcohol is derived from fruits such as apricots.
EU Allergen
Citronellol is used to add fragrance/parfum to a product. It is often derived from plants such as roses. In fact, it can be found in many essential oils including geranium, lavender, neroli, and more. The scent of Citronellol is often described as "fresh, grassy, and citrus-like".
EU Allergen
Benzyl Benzoate is usually created from the condensation of benzoic acid and benzyl alcohol. It is used as a preservative, solvent, and has a floral/balsamic scent in large amounts.
Potassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.
Antioxidant 4 Benefits May cause irritation
Tocopherol (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.
4 Benefits 2 Concerns
Citric Acid is an AHA derived from citrus fruits (think oranges, lemons, and limes!).
Xanthan 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.
2 Concerns
Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.
Water, Cocos Nucifera Oil, Amodimethicone, Polyquaternium-37, Phenoxyethanol, Propylene Glycol Dicaprylate/Dicaprate, Xylitylglucoside, Sodium Hydroxide, Anhydroxylitol, Xylitol, Dimethicone Peg-7 Phosphate, Ppg-1 Trideceth-6, Trideceth-6, Behentrimonium Chloride, Limonene, Xylose, Ethylhexylglycerin, Sorbitan Oleate, Linalool, Isopropyl Alcohol, Cetrimonium Chloride, Glycerin, Hydrolyzed Vegetable Protein Pg-Propyl Silanetriol, Benzyl Salicylate, Coumarin, Zingiber Officinale Root Extract, Citral, Benzyl Alcohol, Citronellol, Benzyl Benzoate, Leontopodium Alpinum Callus Culture Extract, Potassium Sorbate, Tocopherol, Citric Acid, Xanthan Gum, Dipeptide Diaminobutyroyl Benzylamide Diacetate, Parfum
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.
Propanediol helps absorb ingredients into your skin, boosting their benefits. It can act as an emollient, making your skin softer. Propanediol can help products last longer by boosting the properties of preservatives within the formulation.
Betaine 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.
Sodium Hyaluronate is hyaluronic acid's salt form. It is commonly derived from the sodium salt of hyaluronic acid.
This ingredient is a preservative, antimicrobial, and emulsifier. It is often used in cosmetics for its ability to cleanse, condition, and reduce static.
Panthenol is a common ingredient that helps hydrate and soothe the skin. It can be found naturally in our skin and hair.
Hydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.
Pvp is a water-soluble synthetic polymer and common hairstyling ingredient. It is a film-forming ingredient and used to "hold" specific shapes of hair.
This ingredient is created from dehydrating xylitol in acidic conditions. Xylitol is a famous sugar and humectant.
4 Benefits 2 Concerns
Citric Acid is an AHA derived from citrus fruits (think oranges, lemons, and limes!).
May worsen Eczema
Sorbic Acid is a preservative. It is the most commonly used food preservative in the world.
Phenoxyethanol 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.
Ethylhexylglycerin (we can't pronounce this either) is commonly used as a preservative and skin softener. It is derived from glyceryl.
Sodium 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.
2 Concerns
Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.
EU Allergen
Citral is a fragrance and used to add a lemon-like scent to products. It is both naturally found in plants and created synthetically. In plants, it is commonly occurring in lemon myrtle, lemongrass, lemon tea-tree, lemon verbena, and other citruses.
EU Allergen
Citronellol is used to add fragrance/parfum to a product. It is often derived from plants such as roses. In fact, it can be found in many essential oils including geranium, lavender, neroli, and more. The scent of Citronellol is often described as "fresh, grassy, and citrus-like".
EU Allergen
Hexyl Cinnamal is a fragrance ingredient with a similar scent to jasmine. It can be naturally found in chamomile essential oil.
Limonene is a fragrance that adds scent and taste to a formulation.
2 Concerns
Linalool is a fragrance and helps add scent to products. It's derived from common plants such as cinnamon, mint, citrus, and lavender.
Water, Propanediol, Betaine, Quaternium-22, Sodium Hyaluronate, Bis-Aminopropyl Diglycol Dimaleate, Cetrimonium Chloride, Panthenol, Hydroxyethylcellulose, Pvp, Guar Hydroxypropyltrimonium Chloride, Furcellaria Lumbricalis Extract, Pelvetia Canaliculata Extract, Xylitylglucoside, Polyquaternium-44, Anhydroxylitol, Maltitol, Citric Acid, Trisodium Ethylenediamine Disuccinate, Xylitol, Sorbic Acid, Phenoxyethanol, Ethylhexylglycerin, Sodium Benzoate, Parfum, Citral, Citronellol, Hexyl Cinnamal, Limonene, Linalool
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 WaterPhenoxyethanol 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.
Xylitylglucoside is created from xylitol and glucose, two humectants.
Not surprisingly, this ingredient is also a humectant. It attracts and holds water in your skin, helping to maintain hydration.
This ingredient is most commonly found in a popular trio called Aquaxyl. Aquaxyl is made up of anhydroxylitol(24 - 34%), xylitylglucoside (35 - 50%), and xylitol (5 - 15%).
According to a manufacturer, Aquaxyl is known for a 3-D hydration concept and an anti-dehydration shield to reinforce the outer layer of skin.
Learn more about XylitylglucosideThis ingredient is created from dehydrating xylitol in acidic conditions. Xylitol is a famous sugar and humectant.
Much like its predecessor, anhydroxylitol is a humectant. Humectants attract and hold water to moisturize the skin.
This ingredient is most commonly found in a popular trio called Aquaxyl. Aquaxyl is made up of anhydroxylitol (24 - 34%), xylitylglucoside (35 - 50%), and xylitol (5 - 15%).
According to a manufacturer, Aquaxyl is known for a 3-D hydration concept and an anti-dehydration shield to reinforce the outer layer of skin.
This ingredient is often derived from plants such as wood and sugarcane.
Learn more about AnhydroxylitolXylitol is a humectant and prebiotic. It can help with dry skin.
In studies, xylitol has been shown to improve dry skin. It decreased transepidermal water loss, or when water passes through the skin and evaporates. Xylitol also showed to help improve the biomechanical properties of the skin barrier.
The prebiotic property of xylitol may also help reinforce our skin's natural microbiome. Having a healthy microbiome prevents infection by bad bacteria and helps with hydration.
As a humectant, Xylitol helps draw moisture from both the air and from deeper skin layers. This helps keep skin hydrated.
Xylitol is a sugar alcohol and commonly used as a sugar substitute. It is naturally occurring in plants such as strawberries and pumpkin.
Learn more about XylitolLimonene is a fragrance that adds scent and taste to a formulation.
It's found in the peel oil of citrus fruits and other plants such as lavender and eucalyptus. The scent of limonene is generally described as "sweet citrus".
Limonene acts as an antioxidant, meaning it helps neutralize free radicals.
When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin.
The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.
Learn more about LimoneneEthylhexylglycerin (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.
Linalool is a fragrance and helps add scent to products. It's derived from common plants such as cinnamon, mint, citrus, and lavender.
Linalool has the same effect as Limonene when exposed to air. Oxidized linalool can cause allergies and skin sensitivity.
Linalool has a scent that is floral, spicy tropical, and citrus-like.
Learn more about LinaloolThis ingredient is a preservative, antimicrobial, and emulsifier. It is often used in cosmetics for its ability to cleanse, condition, and reduce static.
Cetrimonium chloride is a quaternary ammonium salt, meaning it has a water-soluble structure.
Citral is a fragrance and used to add a lemon-like scent to products. It is both naturally found in plants and created synthetically. In plants, it is commonly occurring in lemon myrtle, lemongrass, lemon tea-tree, lemon verbena, and other citruses.
The EU mandates Citral be listed separately as a fragrance. It is a known allergen and may cause contact dermatitis. Citral can also used as a masking ingredient.
The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.
The term 'citral' is a collective term for two geometric isomers: geranial/Citral A and neral/Citral B.
Learn more about CitralCitronellol is used to add fragrance/parfum to a product. It is often derived from plants such as roses. In fact, it can be found in many essential oils including geranium, lavender, neroli, and more. The scent of Citronellol is often described as "fresh, grassy, and citrus-like".
Since the Citronellol molecule is already unstable, Citronellol becomes irritating on the skin when exposed to air.
Citronellol is a modified terpene. Terpenes are unsaturated hydrocarbons found in plants. They make up the primary part of essential oils.
Citronellol is not able to be absorbed into deeper layers of the skin. It has low permeability,
Citronellol is also a natural insect repellent.
Learn more about CitronellolCitric Acid is an AHA derived from citrus fruits (think oranges, lemons, and limes!).
As an AHA, Citric Acid removes the top layer of skin cells from the newer layer of skin underneath. This helps skin to remove dark spots and even out skin tone.
If you spot Citric Acid near the end of an ingredient list, it's likely there as a pH adjuster rather than an active ingredient.
Read more about some other popular AHA's here:
Learn more about Citric AcidParfum is a catch-all term for an ingredient or more that is used to give a scent to products.
Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.
In the US, the alternative name for parfum is 'fragrance'.
The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.
For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.
One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.
Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.
Parfum can also be used to mask or cover an unpleasant scent.
The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.
Learn more about ParfumIngredient Ratings
Here's what our community thinks of the ingredients in these two products.
When to use
Kérastase Défense Thermique Heat Protecting Leave-In Treatment for Weakened Hair 37 ingredients
Olaplex Nº.9 Bond Protector Nourishing Hair Serum 30 ingredients
Reviews
Here's what our community thinks
