Kérastase Défense Thermique Heat Protecting Leave-In Treatment for Weakened Hair Versus Kérastase Defense Thermique Blow Dry Primer
Updated on November 03, 2023
Overview
What they are
These products are both reef safe heat protectants. They have a total of 37 ingredients in common
Cool Features
They both contain peptides and Vitamin E
Suited For
They're both likely to be good for anti aging, dry skin, brightening skin and scar healing
Free From
They both do not contain any parabens or sulfates
What's Inside
They both contain harsh alcohols, common allergens, fragrances, oils and 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
Kérastase Défense Thermique Heat Protecting Leave-In Treatment for Weakened Hair 37 ingredients
Kérastase Defense Thermique Blow Dry Primer 38 ingredients
About this product
About this product
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
Kérastase Defense Thermique Blow Dry Primer 38 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 WaterCocos Nucifera Oil is obtained from the kernels of the coconut fruit. In other words, this is coconut oil.
Coconut Oil is rich in fatty acids with lauric acid making up the majority of these. It also contains linoleic acid. Due to this high fatty acid content, coconut oil helps trap moisture and soften skin.
Despite being antibacterial, coconut oil may not be great for acne-prone skin. It is comedogenic and may clog pores. This ingredient may not be safe for malassezia or fungal acne.
Note: Coconut Oil should not replace your sunscreen for UV protection. Studies show it only blocks about 20% of UV.
This oil is non-volatile and has a light scent.
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 Cocos Nucifera OilThis water-soluble silicone is used for its hydrating and softening properties. It is used to add a silky feel to skincare products and has great benefits for haircare.
In haircare, this ingredient:
- Adds shine
- Protects color
- Offers thermal protection
- Boosts hair strength
- Does not build up as easily
We don't have a description for Polyquaternium-37 yet.
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.
It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.
Propylene Glycol Dicaprylate/Dicaprate is a mixture of Propylene Glycol Dicaprylate and Propylene Glycol Dicaprate.
It is an emollient and helps hydate the skin.
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 XylitylglucosideSodium 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 HydroxideThis 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 XylitolWe don't have a description for Dimethicone PEG-7 Phosphate yet.
We don't have a description for PPG-1 Trideceth-6 yet.
We don't have a description for Trideceth-6 yet.
This ingredient is a preservative and often used for it's anti-static properties. You'll most likely see this ingredient in hair conditioners.
It does not cause irritation or sensitization in leave-on products at 1-5%.
Limonene 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 LimoneneWe don't have a description for Xylose yet.
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.
Sorbitan Oleate is created from compounds in oleic acid and sorbitol.
It is used to stabilize a product by preventing ingredients from separating. Emulsifiers help keep ingredients together, such as oils and water.
According to a manufacturer, the ingredient Sorbitan Monooleate shares an INCI name with this one.
Sorbitan Oleate may not be fungal acne safe. It can also worsen oily skin.
Learn more about Sorbitan OleateLinalool is a fragrance and helps add scent to products. It's derived from common plants such as cinnamon, mint, citrus, and lavender.
Like Limonene, this ingredient oxidizes when exposed to air. Oxidized linalool can cause allergies and skin sensitivity.
This ingredient has a scent that is floral, spicy tropical, and citrus-like.
Learn more about LinaloolIsopropyl 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 an astringent alcohol. Astringent alcohols may also irritate skin as they high amounts may strip away your skin's natural oils.
Other types of astringent alcohols include:
According to the National Rosacea Society based in the US, you should be mindful of products with these alcohols in the top half of ingredients.
Any type of sanitizing product will have high amounts of alcohol to help kill bacteria and viruses.
Learn more about Isopropyl AlcoholThis 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.
Glycerin 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 GlycerinWe don't have a description for Hydrolyzed Vegetable Protein Pg-Propyl Silanetriol yet.
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.
In fragrances, Benzyl Salicylate may be a solvent or a fragrance component. In synthetic musk scents, it is used as a solvent. For floral fragrances such as lilac and jasmine, it is used as a fragrance component. The natural scent of Benzyl Salicylate is described as "lightly-sweet, slightly balsamic".
While Benzyl Salicylate has been associated with contact dermatitis and allergies, emerging studies show it may not be caused by this ingredient alone.
However, this ingredient is often used with fragrances and other components that may cause allergies. It is still listed as a known allergen in the EU. We recommend speaking with a professional if you have concerns.
Another study from 2021 shows Benzyl Salicylate may have anti-inflammatory properties.
Learn more about Benzyl SalicylateCoumarins are a group of substances found naturally in plants. There are over 1300 types of coumarins identified. It has a natural vanilla scent.
Coumarin is an identified EU known allergy, meaning it may cause an allergic reaction when applied to the skin.
In many countries, coumarin is banned as a food additive. However, it can be found in soaps, tobacco products, and some alcohol drinks.
Plants use coumarins as a chemical defense. Some plants that have coumarins include lavender, tonka beans, and yellow clovers.
Learn more about CoumarinZingiber Officinale is more commonly known as ginger.
Ginger root has antioxidant, anti-inflammation, and antimicrobial properties.
The antioxidant properties help protect your body from free-radicals. Free-radicals are molecules that may damage your skin cells. As a result, ginger may help slow down signs of aging such as hyperpigmentation and wrinkles.
Studies show ginger inhibits the enzyme that breaks down collagen. It also helps with:
This ingredient has no negative side-effects and is safe to use unless one has a specific allergy to it.
Ginger originates from Southeast Asia but has spread throughout the world. It is now a common spice used in many cultures.
Learn more about Zingiber Officinale Root ExtractCitral 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 CitralBenzyl 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.
Benzyl Alcohol has both antibacterial and antioxidant properties. These properties help lengthen the shelf life of products. Benzyl Alcohol is a solvent and helps dissolve other ingredients. It can also improve the texture and spreadability.
Alcohol comes in many different forms. Different types of alcohol will have different effects on skin. This ingredient is an astringent alcohol.
Using high concentrations of these alcohols are drying on the skin. They may strip away your skin's natural oils and even damage your skin barrier. Astringent alcohols may also irritate skin.
Other types of astringent alcohols include:
According to the National Rosacea Society based in the US, you should be mindful of products with these alcohols in the top half of ingredients.
Any type of sanitizing product will have high amounts of alcohol to help kill bacteria and viruses.
Learn more about Benzyl AlcoholCitronellol 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 CitronellolBenzyl 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.
As a preservative, Benzyl Benzoate works against bacteria and fungus. It is often used to treat scabies and lice in medicine.
Solvents are used to keep ingredients together in a product. They can help dissolve ingredients to stable bases or help evenly distribute ingredients throughout the product.
Due to its fragrance, Benzyl Benzoate can be sensitizing and may cause contact dermatitis. It is a known EU allergen. We recommend speaking with a professional if you have any concerns.
Benzyl Benzoate can be naturally found in cranberries and peaches.
Learn more about Benzyl BenzoateLeontopodium Alpinum Callus Culture Extract is an antioxidant.
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 SorbateTocopherol (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 TocopherolCitric 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 AcidXanthan 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 GumThis 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 DiacetateParfum 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.
For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.
The term 'parfum' or '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
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