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Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
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Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
Defense Thermique - K Loyalty Club - 15% | L'Oréal Partner Shop
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Description

Genesis is the first dual action anti-fall haircare range: FOR ALL WOMEN, IN ALL LIFESTYLES, WITH ALL DEGREE OF HAIR FALL.
Powered with a cocktail of highly efficient ingredients to instantly strengthen and thicken the hair fiber for an immediate fuller look with more fiber strength, more fiber retention* and -84% less hair-fall**.

 

*Clinical study, 99 people, 6 weeks use.
**hair-fall due to breakage. Instrumental test on Bain Nutri-fortifiant + Masque Reconstituant + Ampoule/Sérum Aminexil.

 

HOW DOES GENESIS  WORK?
A double action for your client: 
Instantly: PROTECTS AGAINST DAILY EXTERNAL AGGRESSOR AND ANTIOXIDES thanks to Ginger roots and Edelweiss native cells.
Long Term: STOP HAIR-FALL FORTIFIES HAIR ANCHORAGE & RETENTION AND REDUCE HAIR-FALL FROM THE ROOTS thanks to Aminexil.

 

Défense Thermique benefits:
- Detangles and hydrates without frizz. 
- 24H protection against frizz even in high conditions of humidity. 
- Protects hair from blow-dry heat. 
- Helps to prevent split ends. 
- Leaves hair shiny and silky. 
- 99% less hair fall due to breakage from brushing*. 
- 49% softer hair*.

*After application of Défense Thermique.

 

WHO IS IT FOR? 
Genesis targets every woman with hair fall need that would be efficient, convenient and pleasurable with :
- Instant result of hair care
- Efficacy of anti-hair fall solutions

How To Use

Prime with the Défense Thermique :

Step 1: Apply on wet lengths.
Step 2: Blow dry.
In case of contact with eyes, rinse them immediately and thoroughly.

 

Learn more on Access

Ask more information about this product
Ingredients

Genesis Défense Thermique is enriched with GINGER ROOT and EDELWEISS NATIVE CELLS.

GINGER ROOTS: Known for its ability to protect against daily external aggressors.

EDELWEISS NATIVE CELLS: Capable to resist the most extreme conditions and is known in skincare for its antioxidants. It also has power & collagen-preserving properties.


INGREDIENTS
AQUA / WATER / EAU • COCOS NUCIFERA OIL / COCONUT 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 / GINGER 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 / FRAGRANCE

Rating & Reviews

1,186 reviews
5 stars
( 863)
4 stars
( 212)
3 stars
( 60)
2 stars
( 19)
1 star
( 32)
5
4.6 / 5 stars

Marisabel

1

1.760041532E12 09/10/2025

heavy for blow hair

does not work for my hair - I am feeling my hair heavy

Originaly posted on  kerastase.ca

Reply from BEC 09/10/2025

Thanks for reaching out to Kerastase! We're sorry to hear you're not completely satisfied with our Genesis Défense Thermique. If you would like assistance with your purchase or with choosing a more suitable product, we encourage you to go to our website and chat with a Hair Specialist. We are available Monday to Friday from 10 AM to 9 PM EST and on Saturday and Sunday from 12 PM to 8 PM EST. We look forward to assisting you!

Linh

5

1.75992751E12 08/10/2025

The best scent for my hair !!!!

My hair appears more shiny and silky after using it. I would love to have a hair perfume of this scent!! Just obsessed!! Please do!!

Originaly posted on  kerastase.ca

Rachel Peach

5

1.759429808E12 02/10/2025

Smooth

This is the most amazing leave in conditioning heat protectant spray. I use it before blow drying and it helps protect my hair! Can not live without it! Makes my hair silky smooth!

Originaly posted on  kerastase-usa.com

Desiree3351

4

1.759418113E12 02/10/2025

good at detangiling

ive only used it twice. A little goes a long way. helped detangle my hair immediently to brush. Need to use more to see if it helps with breakage

Originaly posted on  kerastase-usa.com

tiadesaii_525

5

1.759402807E12 02/10/2025

HEAT PROTECTANT

[This review was collected as part of a promotion.] Kérastase Heat Defense Crème provides excellent protection against heat damage while strengthening and smoothing hair strands. It leaves hair feeling soft, resilient, and frizz-free with a lightweight finish. Ideal for daily styling, it helps maintain hair health and shine, making it a must-have in any professional haircare routine

Originaly posted on  influenster.com

Luna25

5

1.759149009E12 29/09/2025

I love this product!

The Genesis Défense Thermique Heat Protecting Spray is amazing! It smells great, keeps my hair soft and shiny, and protects perfectly from heat without feeling heavy or greasy. A must-have in my routine!

Originaly posted on  kerastase-usa.com

Mandi 8

3

1.759265619E12 30/09/2025

Mixed feelings

Works great but the scent is too strong for asthma sufferers.

Originaly posted on  kerastase-usa.com

Reply from Consumer Care Center 30/09/2025

It's great to hear our Thermique Heat Protecting Spray "works great" for you! However, we're very sorry the strong scent is an issue for your asthma. We truly appreciate this crucial feedback and will pass it on to our product development team.

agent_tiffany_3396

4

1.759102205E12 28/09/2025

Good, but too expensive

[This review was collected as part of a promotion.] It’s fine for what it is, it does pretty much the same thing as every other moisturizing heat protector, and it does work as you can see. But for how expensive it is, I just don’t think it’s worth the cost. Also it just squirts. I prefer to mist products like this so that it covers more of the hair without over saturating one section. Misting just gives a more even application and reduces product waste.

Originaly posted on  influenster.com

272727

5

1.759072509E12 28/09/2025

Good product

I like it. Makes my hair a little heavier what I wanted, smells like a parfum. My hair step by step looks not so dry like it was before. I ordered another one to try.

Originaly posted on  kerastase-usa.com

MaggieFer

5

1.75907161E12 28/09/2025

better than other brands on the market

I pass for breastfeeding this year and my hair was broken, I been seen a difference in my hair it feels more soft , i just have to wait for the little hairs to growth again, I keep buying the products

Originaly posted on  kerastase-usa.com

LisaBru

5

1.759008605E12 27/09/2025

Awesome hair product!

[This review was collected as part of a promotion.] This product makes my hair feel silky and shiny. A great add to my hair routine!

Originaly posted on  kerastase-usa.com

TBert101

5

1.759005006E12 27/09/2025

Took a chance and glad I did

This is a great hair protectant. Light doesn’t weigh down hair.

Originaly posted on  kerastase-usa.com

Hair12

5

1.758983407E12 27/09/2025

Awesome

[This review was collected as part of a promotion.] Works wonderfully on dry hair!!!!!. Will buy again

Originaly posted on  kerastase-usa.com

Katharyn

5

1.758848404E12 25/09/2025

Turn up the heat!

[This review was collected as part of a promotion.] I apply this to my damp hair prior to heat styling and it seems to protect it from damage and adds shine and a lovely scent

Originaly posted on  kerastase-usa.com

miss_morgs_6102

5

1.758848404E12 25/09/2025

great for fine hair girlies

[This review was collected as part of a promotion.] Fine hair girlies unite!! This is one of my favorite heat protectants. The mist on the sprayer is super fine so it allows the product to EVENLY coat my hair (which is one of my biggest gripes with the packaging on other products) so it doesn’t get over-saturated in certain areas. It’s also super lightweight so my hair doesn’t get weighed down or greasy looking when I’m done blow drying. Also smells amazing. Highly recommend

Originaly posted on  influenster.com

Ksdksd

5

1.758848404E12 25/09/2025

Love the Genesis leave on spray

[This review was collected as part of a promotion.] My hair stylist recommended this Kerastase product to me for my weak and damaged hair. I love how it has made my hair feel; sleek, stronger and gets detangled

Originaly posted on  kerastase-usa.com

Kelly Hall

5

1.758814206E12 25/09/2025

Heat Protecting Spray: Excellent

[This review was collected as part of a promotion.] Wonderful protecting spray! I have tried many and this is by far, the best. Very pleasant fragrance, too!

Originaly posted on  kerastase-usa.com

brittbon13_6231

4

1.758812409E12 25/09/2025

Smell is very pleasant

[This review was collected as part of a promotion.] It has such a lightweight, beautiful smell. That’s the first thing I noticed about this! The product itself if a nice milky texture. I personally like to spray it in my hands, rub together, and distribute throughout my hair. The nozzle is so satisfying when sprayed though if that’s your preference! I don’t blow dry my hair often so can’t speak to heat protection exactly, but it still worked great for air drying! I would personally use it just for the smell alone - it’s like a hair perfume!

Originaly posted on  influenster.com

TracyB

5

1.758717009E12 24/09/2025

Love this !

I use this daily before styling my hair, it makes my hair silky, protecting from the heat I use daily.

Originaly posted on  kerastase-usa.com

jordanl105_6624

5

1.758652209E12 23/09/2025

My new blow dry go-to!

[This review was collected as part of a promotion.] Got this free from Influenster and started using it with my Kerastase night serum. Honestly obsessed — look how smooth my hair is!! it smells amazing, makes my hair soft, and I don’t get nearly as much breakage when I blow dry. Totally worth the price, like every other Kerastase product I’ve tried!

Originaly posted on  influenster.com

Hart13

4

1.758557708E12 22/09/2025

Love this product

[This review was collected as part of a promotion.] It really does helps protect hair from further damage.

Originaly posted on  kerastase-usa.com

Big fan of Kerastase

5

1.758500105E12 21/09/2025

So good!!

[This review was collected as part of a promotion.] This thermic is a must! Never again use hot tools on my hair with out it

Originaly posted on  kerastase-usa.com

Rachelmrg

5

1.758485706E12 21/09/2025

Love it

Using it for over 6 months , works really good on my hair

Originaly posted on  kerastase-usa.com

sawyern_1271

5

1.758483008E12 21/09/2025

Smells Amazing

[This review was collected as part of a promotion.] This stuff smells amazing and makes my hair smell nice all day. I don’t use a lot of heat on my hair besides blow drying, but I love using this. The spray is a little heavy due to how thick the liquid is so sometimes it’s hard to not get a ton of product in one spot. I will for sure use all of this product and if I need another heat protectant spray, this will be one of my top choices!

Originaly posted on  influenster.com

Anonymous

5

1.758471308E12 21/09/2025

Amazing!

This heat protecting spray is amazing! It works so well and smells so good-- it smells just like my hair after leaving the salon! It also makes my hair super soft too which i love! I will definitely be repurchasing this item!

Originaly posted on  kerastase-usa.com

juliannek11_8199

4

1.758302107E12 19/09/2025

Smells so good

[This review was collected as part of a promotion.] Smells so good! I will say you have to use a bunch for it to work but if you really soak your hair in it it’ll do its job and protect my hair from the heat!

Originaly posted on  influenster.com

Capassi

5

1.758249903E12 18/09/2025

Perfect

[This review was collected as part of a promotion.] This product is what I was looking for. My hair was so dry and thin and now it’s perfect.

Originaly posted on  kerastase-usa.com

jrost18

5

1.758157204E12 17/09/2025

Great for brushing knots out

[This review was collected as part of a promotion.] My fine hair gets very knotted after showering, even after brushing, and this product helps smooth my hair right out. I use it on damp hair and blow it out, and it dries out so soft.

Originaly posted on  kerastase-usa.com

acorncharm_3013

4

1.758142805E12 17/09/2025

Softer, voluminous hair but greasy sooner too

[This review was collected as part of a promotion.] The consistency of this is similar to a leave-in conditioner spray, maybe a littler thicker. It smells lovely and it’s easy to spray over my hair. It seems like the main two benefits it advertises is heat protection and reducing breakage. I’ve used it a couple times now and I would cover my hair, brush, and then blow dry. I think in terms of breakage reduction, I didn’t notice any major difference. Maybe that’s something that takes long term use to see. I did notice my hair seemed more voluminous and softer after blow drying. My only complaint is that the times that I used it, it felt like my hair got greasy faster than normal. Usually I can go about three days without washing my hair, and it felt like I needed to wash it in two with this. I should also mention I don’t really focus the roots with this either so I found it to be strange.

Originaly posted on  influenster.com

dcoenen_5993

5

1.75805101E12 16/09/2025

Has transformed my blow out

[This review was collected as part of a promotion.] I’ve been using Kérastase Défense Thermique for a few weeks now, and I’m really impressed. My hair tends to get dry and frizzy when I blow-dry or straighten, but this feels so lightweight and smooths everything out without making it greasy or heavy. I noticed less breakage when brushing after heat styling, and my ends look healthier. It also makes my hair feel soft and silky, almost like I had a salon treatment. For me, it’s been a game-changer for protecting my hair and keeping it looking polished.

Originaly posted on  influenster.com

erican1_3225

5

1.758060006E12 16/09/2025

Easy Protection and Shine

[This review was collected as part of a promotion.] I really enjoyed this smoothing heat protectant spray. It has a subtle scent and is easy to apply. After blow drying, curling, and touching up my hair it still felt healthy and protected.

Originaly posted on  influenster.com

lylyn4_3351

2

1.758025813E12 16/09/2025

Not for me

[This review was collected as part of a promotion.] Heavily fragranced so avoid this if you're sensitive to scents. Too heavy for my hair type and weighs it down. May work on thick/coarse hair if used sparingly.

Originaly posted on  influenster.com

chrissit84_1880

4

1.757990704E12 15/09/2025

He;ps with breakage

[This review was collected as part of a promotion.] I liked this product. I have somewhat thinner hair and it can end up being damaged by things like heat (hello blow drying) and hair ties. So something that adds a layer of protection on the days when I do need to dry my hair before heading out the door is very much welcomed. I found that the spray on this was a bit wilder than I originally expected, but I also just chopped off 12+ inches of hair so that may be me still adjusting. Not a crazy strong smell, this product did drop the percentage of breakage I had been seeing. Happy to keep using this when I dry my hair.

Originaly posted on  influenster.com

sarahp695_8217

5

1.758028509E12 16/09/2025

Soft and smooth

[This review was collected as part of a promotion.] This product smells so good and helps reduce hair frizz!! It also made my hair softer :) very easy to use as well and comes out like a fine mist! Love that it protects from heat

Originaly posted on  influenster.com

katier309_4805

4

1.758028509E12 16/09/2025

Good for fine hair

[This review was collected as part of a promotion.] This product is nice and lightweight, with a pleasant but not overpowering scent. It doesn’t weigh down my oily fine hair and keeps my ends from being damaged due to constant heat from my hairdryer. The packaging is sleek and I would consider this a good value for how long the bottle will last!

Originaly posted on  influenster.com

megandb94a_2060

5

1.758033011E12 16/09/2025

Good product

[This review was collected as part of a promotion.] It smells good and is easy to use. The bottle lasts a long time. It also gives a little bit of a lemon scent. Heat protection is always a nice addition to your hair routine.

Originaly posted on  influenster.com

melissawinch_4811

4

1.758028509E12 16/09/2025

Great heat protectant

[This review was collected as part of a promotion.] This stuff is great! Sprays well and distributes after brushing in hair. Packaging is simple. Ingredients are ok and scent is outrageously strong. It protects my hair from heat but not quite sure it’s worth the price.

Originaly posted on  influenster.com

caitlinm160_8148

4

1.758028509E12 16/09/2025

Smells amazing

[This review was collected as part of a promotion.] This smells so nice. It works well especially after I got color and my hair needs moisture. Depending on the price, not sure this is an absolute necessity for me to buy in the future.

Originaly posted on  influenster.com

tuchau_1384

5

1.75796101E12 15/09/2025

Helps create volume, makes my hair look shiny and

[This review was collected as part of a promotion.] I like how my hair looks and feels after using the karastase genesis defense thermique heat protecting spray. It helps create volume, makes my hair look shiny and less frizzy. The spray is light and absorbs quickly, so it doesn’t feel greasy or heavy after using. I also like the smell of the product. I paired it with the karastase genesis shampoo and conditioner and received great result.

Originaly posted on  influenster.com

amandas1454_3225

5

1.757943909E12 15/09/2025

Leaves hair feeling, looking, and smelling great.

[This review was collected as part of a promotion.] Let’s talk smell, this smells go good! The first time I used it I really debated on whether or not I needed to wear perfume that day. The nozzle sprays very well and evenly. My hair did not feel heavy or weighed down. It made my hair very soft and shiny. I do not blow dry my hair often but when I do I will reach for this again!!

Originaly posted on  influenster.com

tlmla_3796

5

1.757914209E12 15/09/2025

Smells great and reduces frizz!

[This review was collected as part of a promotion.] Smells absolutely amazing! A little bit goes a long way for the price and the product does a great job of reducing frizz from constantly using my hair straightener. The packaging is simple and the product itself is a bit watery, so be careful when dispensing.

Originaly posted on  influenster.com

nania22_9151

3

1.757943909E12 15/09/2025

Nice smell

[This review was collected as part of a promotion.] Just okay. This product did not work great for my hair. I really liked the smell and although my hair looked good after straightening it, it also felt stringy after application.

Originaly posted on  influenster.com

allir38_2259

5

1.757943909E12 15/09/2025

Nice scent. Left my hair soft and shiny. Goodbye,

[This review was collected as part of a promotion.] I enjoyed this product, and it is now a staple in my hair routine. I feel that it has been very effective at protecting my hair from heat and damage. My hair was noticeably less frizzy after blow drying and left my hair soft and glossy. The scent is not overpowering and has a nice fragrance. Well worth every penny. The pretty pink bottle looks nice sitting on my counter.

Originaly posted on  influenster.com

kiersteng7_961

2

1.75804035E12 16/09/2025

Could be better

[This review was collected as part of a promotion.] I was pretty underwhelmed with this heat spray. I didn’t like the smell, the instructions weren’t clear on when to use it in relation to other products, and my hair still ended up the same amount of frizzy as when I don’t use it. I will say the smell after blow drying was way better than the original smell and it did make my hair soft, but for curly hair I’d prefer something better for texture and that holds the curls.

Originaly posted on  influenster.com

Reply from Consumer Care Center 16/09/2025

Thank you for your detailed feedback on our heat spray. We're sorry it underwhelmed you, didn't control frizz, and lacked clear instructions for use. While you noted improved scent post-blow-dry and hair softness, we understand your need for better texture and curl hold for curly hair. Your insights are invaluable for our improvements.

mirandac176_2239

5

1.75794301E12 15/09/2025

Good Blowdry Heat Protectant Option

[This review was collected as part of a promotion.] Love the for when I blow dry my hair and need a heat protectant! Feels lightweight and has a rose smell to it. Just wish the nozzle was snore of a mist versus direct spray.

Originaly posted on  influenster.com

nicoleeelauren_6335

5

1.757886305E12 14/09/2025

Love this

[This review was collected as part of a promotion.] The Kérastase Genesis Défense Thermique Heat Protectant Spray is a luxurious yet highly effective product for anyone who regularly styles their hair with heat. It’s lightweight, non-greasy, and distributes evenly, leaving hair feeling soft and silky without weighing it down. The spray provides reliable protection up to high temperatures, helping to prevent breakage and split ends while adding a subtle healthy shine. The scent is classic Kérastase—clean, fresh, and salon-like—which makes the styling experience feel indulgent. Over time, hair looks noticeably smoother and stronger, especially when paired with other Genesis products. If you’re looking for a heat protectant that also nurtures and strengthens your hair, this spray delivers on both performance and luxury

Originaly posted on  influenster.com

allisonb233_7059

4

1.757861109E12 14/09/2025

Effective and smells good!

[This review was collected as part of a promotion.] I really like this spray. I blow out my hair frequently and it has helped protect it from more damage. It also smells really good and has made my hair soft!

Originaly posted on  influenster.com

poetickat_6984

5

1.757828709E12 14/09/2025

Shiny healthy hair after heat!

[This review was collected as part of a promotion.] My hair feels so healthy and shiny and soft when I use this product before I blow dry. The smell is also incredible! My hair stylist mentioned just today how good I smelled and it was all this hair product! A little goes a long way and the pink color looks so cute on my shelf. Highly recommend!!

Originaly posted on  influenster.com

ashleyo364_9765

5

1.757861109E12 14/09/2025

Worth every penny

[This review was collected as part of a promotion.] This stuff is so great. I am on a healthy hair journey, and this has been so important in protecting my hair from heat damage! It doesn’t smell weird like some other heat protectants. The packaging makes it easy to use and the bottle lasts such a long time. I’ve repurchased it already and am going to again once I run out!

Originaly posted on  influenster.com

dozykitten_6900

5

1.757818806E12 13/09/2025

Great product that delivers protection and moistur

[This review was collected as part of a promotion.] I love this product! Amazing scent and very effective. Not only did it protect my hair from damage but it also gave it a nice condition and gloss. It's on the higher side price wise but I would say very worth it!

Originaly posted on  influenster.com

alyssad170_7046

5

1.757808909E12 13/09/2025

Love

[This review was collected as part of a promotion.] Smell is amazing! Fresh and fruity. Not too strong. Seems to be a lightweight spray. I’ve only used a few times so can’t tell long term if it protects my hair, but seems awesome so far!

Originaly posted on  influenster.com

alyssag7_4750

5

1.757808909E12 13/09/2025

Worked and smelled great

[This review was collected as part of a promotion.] I think this spray worked very well and helped keep my hair with as minimal frizz as possible while in some extreme humidity. It also had a great smell.

Originaly posted on  influenster.com

shelleyk14_8388

5

1.757784606E12 13/09/2025

Tames the frizz

[This review was collected as part of a promotion.] I’ve been using the Kérastase Genesis Défense Thermique and it works well. It helps to detangle my fine hair. The scent is fresh and almost citrusy. My hair is finally starting to grow back after postpartum hair loss, and I feel like this product has been helping tame frizz. The first time I used it, my hair felt a little crunchy, but I think that was just because I applied too much. With the right amount, it works really well and leaves my hair looking smooth and healthy.

Originaly posted on  influenster.com

meghavij_8611

5

1.75777471E12 13/09/2025

My new go to heat protecting spray for blow dry!

[This review was collected as part of a promotion.] I love Kerastase products and heat protective spray did not disappoint. I use it before blow drying my hair and it makes them feel very smooth and not frizzy. I have fine hair so I have to make sure to use just small amount of product and I only apply it to the roots and very lightly to the hair near rhe scalp. I love the fact it makes my hair feel light weight when I apply it and it smells great. The design of the product and color is very catchy. I have not noticed any difference with it helping with hair breakage but over all I love this heat protecting spray!

Originaly posted on  influenster.com

jennah121_4939

5

1.757741407E12 13/09/2025

Smells like heaven!!

[This review was collected as part of a promotion.] As someone who frequently uses heat / styling products on my hair, I can say with certainty that this product has protected my hair from heat much better than others. I like that it is kinda a leave in conditioner / heat protector. It leaves the hair hydrated and smelling great, but isn’t overly oily or sticky at all.

Originaly posted on  influenster.com

noteelk_1271

5

1.757771109E12 13/09/2025

Love this perfectly pink hair protecter spray!

[This review was collected as part of a promotion.] Me and my teens are obsessed with this heat protector! It smells sooooo good, like addictive, a perfume for the hair. The pink packaging looks aesthetic on my counter. Literally brings me such joy to use and makes my hair smoother without ironing it.

Originaly posted on  influenster.com

sierrawhiskey_2518

4

1.757701805E12 12/09/2025

Great smell, leaves hair silky soft

[This review was collected as part of a promotion.] Smells good, makes my hair super soft and silky, the packaging is slim and easy to store with the rest of my hair products. Product is easy to use, just spray onto wet hair before blow drying. I can’t say if the value for the money is good since I received the product free for an honest review but I have used kerastase products in the past and they’re a bit on the pricey side but extremely effective. I will continue to use this product.

Originaly posted on  influenster.com

sabrinav9474_6230

5

1.757701805E12 12/09/2025

Shiny, smooth, safe

[This review was collected as part of a promotion.] This is nice addition to anyone who uses a blow dryer or heat styling tool. It is a fine mist application and has a very light refreshingly floral smell. My hair was shiny without being weighed down and the frizz reduced. A little goes a long way so for the huge bottle it should last a long time.

Originaly posted on  influenster.com

thespookygoblin_1169

5

1.757655008E12 12/09/2025

Amazing!

[This review was collected as part of a promotion.] I used this every time I blow dried my hair and boy did it really make my hair soft and silky!! The scent was so nice and pleasant, but not too strong, which I enjoyed greatly. The sprayer has a nice fine mist and dispensed evenly. The bottle is also a nice size!

Originaly posted on  influenster.com

tierras8_6796

5

1.757685608E12 12/09/2025

Great for protecting hair from heat styling tools

[This review was collected as part of a promotion.] The Keratase Genesis Defense Thermique Heat Protecting Spray is a game-changer! It leaves hair feeling soft, smooth, and healthy while providing excellent heat protection. Lightweight and non-greasy, it helps reduce breakage and adds a beautiful shine. A must-have for anyone using hot tools regularly.

Originaly posted on  influenster.com

purplelilytaboo_7655

5

1.757655008E12 12/09/2025

Thermal protection

[This review was collected as part of a promotion.] I have been using this heat protecting spray for sometime now and it is really effective. I usually use this after shower, this product is really creamy and provides thermal protection. For my hair I see no frizz while using this spray!

Originaly posted on  influenster.com

sincerelymik_4714

4

1.757655008E12 12/09/2025

Smells Amazing!

[This review was collected as part of a promotion.] This heat protecting spray worked really well on my hair. It left it feeling and looking less frizzy after blow drying and it smells so good! The packing is really nice too and the product sprays out evenly. I will continue to use this.

Originaly posted on  influenster.com

mnguye825_9342

4

1.757644204E12 11/09/2025

Expensive but works

[This review was collected as part of a promotion.] I loved this product. I used this every time I had to blow dry, straighten, or curl my hair. It helped tame the frizz and protected my hair from the heat damage. It left a nice light rose fragrance which was lovely and not too strong. My hair felt smoother on days I used this product. I would recommend getting this product for the benefits, but it is expensive.

Originaly posted on  influenster.com

florc70_7838

5

1.757630707E12 11/09/2025

Lovely

[This review was collected as part of a promotion.] Great packaging; the mist comes out even and you don’t waste any product. The scent is nice and not too strong. I feel my hair much more smooth and silky!

Originaly posted on  influenster.com

julias838_4231

4

1.757644204E12 11/09/2025

Less frizz, smells great!

[This review was collected as part of a promotion.] This heat protecting spray left my hair feeling smooth and less frizzy. Be sure to use the sprayer, I tried using my hands to distribute and it left my hair sticky. The fragrance is light and lasts for a while. I’m sensitive to fragrances and this one didn’t bother me.

Originaly posted on  influenster.com

heavynleighh_6612

5

1.757604609E12 11/09/2025

Protect your hair!

[This review was collected as part of a promotion.] Heat protectant is so important! This one seems to work great! I love that it also helps to repair damaged and weak hair! My hair looks shiny and feels soft after using it!

Originaly posted on  influenster.com

Sarahlacerda

5

1.757593808E12 11/09/2025

You should buy it

I use a lot of hair dryers, and it saves my hair. You can literally feel and see the difference my hair gets even more shiny

Originaly posted on  kerastase-usa.com

dahliaj7_8400

4

1.757604609E12 11/09/2025

Hair perfume and de frizzer

[This review was collected as part of a promotion.] I enjoy the product, I mainly use it to defrizz my hair and as a hair perfume. The scent is lemon-y. I like how it’s in a spray bottle although since I have courser hair, the spray doesn’t spray enough product. Perhaps it’s a user error.

Originaly posted on  influenster.com

gabriellab89_7942

5

1.757601923E12 11/09/2025

Love Kerastase

[This review was collected as part of a promotion.] This is a great and effective product. The packaging is so pretty in pink and the scent is intoxicating. I love and stand by this brand fully and I love the clean ingredients.

Originaly posted on  influenster.com

Marges24

5

1.757544308E12 10/09/2025

Perfect protection

[This review was collected as part of a promotion.] I love this kerastase protecting spray that sort of laminates the hair inorder to protect it from the heat of blow drying. It gives the hair smoother and glossy finish. I don't.style my.hair without applying it first to make sure my hair is safe from damage caused by frequent styling and blow drying.

Originaly posted on  kerastase-usa.com

sarap240_346

5

1.757604609E12 11/09/2025

Great

[This review was collected as part of a promotion.] Really enjoy this brand and this product. It makes my hair soft and glossy. It has a nice soft scent to it that is not overpowering. The packaging is nice and have not had any problems with the sprayer. I recommend this product.

Originaly posted on  influenster.com

annaliseee_1093

5

1.757520035E12 10/09/2025

Effective heat protectant that combats frizz

[This review was collected as part of a promotion.] I thought this spray was very effective at protecting my hair from heat — I blow dry my hair every night and I feel like this was a very effective product in insulating my hair from heat and damage. My hair was noticeably less frizzy after use. I’m not sure I’ve used it enough to gauge whether or not it’s been strengthening my hair, but overall I love the milky texture and subtle scent, and find the heat protectant capability very effective.

Originaly posted on  influenster.com

richab3_1078

5

1.757436408E12 09/09/2025

Smells like a professional salon

[This review was collected as part of a promotion.] I have curly hair, sometimes I blow dry but worry that it should not make it more dry. But kerastase heat protecting spray saves me. It spreads smoothly and smells like a professional salon. I use it on dried hair or even damp hair. I’m loving it.

Originaly posted on  influenster.com

chelss92_857

5

1.757424715E12 09/09/2025

Very nice product

[This review was collected as part of a promotion.] I really like this stuff only wash my hair once a week and I feel like this had a really helped my hair. The scent is nice and the texture is light so it doesn’t weigh down my hair. You don’t need alot so it will last you a long time so it’s definitely worth every penny. The packaging is study and easy to use! I highly recommend trying this out!

Originaly posted on  influenster.com

deanna1313_5589

5

1.757370622E12 08/09/2025

Great product

[This review was collected as part of a promotion.] Keratase heat protecting spray has been great. The product isn’t too heavy so it doesn’t weigh your hair down. Just enough to get through and protect your hair from the heat. Also, helps to detangle mine

Originaly posted on  influenster.com

Gatita

5

1.757278806E12 07/09/2025

Lo mejor

[This review was collected as part of a promotion.] Amo este producto desde la primer puesta en mi cabello e notado la diferencia

Originaly posted on  kerastase-usa.com

Kaelblapa

5

1.757278806E12 07/09/2025

Me encanta

Amo este protector térmico, Facilita mi peinado y desenreda mi cabello después del lavado. Utilizo secador en mi cabello cada dos dias y siento que lo protege bastante,

Originaly posted on  kerastase-usa.com

Aj1982

5

1.757277009E12 07/09/2025

Love it!

[This review was collected as part of a promotion.] My hair has never felt so soft. Its so smooth whether I blow dry it or not. And I have so much less breakage. And I love the smell. Perfect.

Originaly posted on  kerastase-usa.com

Kina15

4

1.757270706E12 07/09/2025

Great!

I really like this product and feel it has helped my hair. It smells great too!

Originaly posted on  kerastase-usa.com

missanita_7267

5

1.757205903E12 06/09/2025

Leave In with Heat Protection

[This review was collected as part of a promotion.] I was totally surprised by this product! It clearly says on the bottle that it’s meant to be used as a heat protector for blow drying. I love the light scent and the fact that I can just spray it on as a leave-in conditioner without weighing my hair down. I’m definitely adding this to my hair collection because of how versatile it is! I use it as just a leave in sometimes to help retain my hair’s moisture

Originaly posted on  influenster.com

katier554_4102

3

1.757433564E12 09/09/2025

Solid heat protectant for wet hair

[This review was collected as part of a promotion.] I wanted to try this product a good amount of times before making my review. TLDR: this is a solid heat protectant. Background: I have thick, long undyed hair. My scalp tends to be on the oilier side and I have to wash my hair 4x/week because of that and my workout schedule. The good: this heat protectant is great when drying my hair when wet or damp. My hair comes out feeling light, bouncy, and shiny. The scent is not overwhelming Where I noticed I don’t absolutely love the end product is when I’m styling my hair when it’s already dry. I feel like my oiliness is accentuated and even made a little worse and i have to end up using dry shampoo So bottom line, if you have oily hair, this product is great when styling your hair from wet/damp, but you may want to look for another option if you often style your hair from dry.

Originaly posted on  influenster.com

Reply from Consumer Care Center 09/09/2025

Thank you so much for your thorough and insightful review! We're delighted to hear that our product serves as a solid heat protectant, making your hair feel light, bouncy, and shiny when styled from wet or damp. We also deeply appreciate your honest feedback that it may accentuate oiliness when used on already dry hair. Your nuanced distinction between its performance on wet versus dry hair, especially for those with an oily scalp, is incredibly valuable.

gamzeg4_3532

3

1.757425787E12 09/09/2025

Nostalgic smell

[This review was collected as part of a promotion.] This spray smells very good, it feels nostalgic for some reason. I don’t know what to say about the heat protection though. I think I will see the impact of this in the long term. I will keep using it!

Originaly posted on  influenster.com

Reply from Consumer Care Center 09/09/2025

Thank you for your lovely review! We're delighted you enjoy the spray's scent and find it nostalgic. We understand that heat protection benefits are often seen over the long term, and we appreciate your plan to continue using the product to observe its full impact. Your positive feedback and commitment mean a lot to us!

marumenen_2026

3

1.757423908E12 09/09/2025

Not so great

[This review was collected as part of a promotion.] Love the smell and the bottle, absolutely obsessed with both. Having used Kerastase before I had great hopes this product would be as amazing as it seems. Unfortunately, I’ve seen better results for a fraction of the price. Yes it gets the job done and makes your hair smell amazing but It feels very dry, I can’t imagine how it would help already damaged hair being so drying, this being said, it absolutely does not help reduce frizz. I have thick long wavy hair and it just didn’t do what it was supposed to for me. Now it says it’s for damaged hair and my hair is very healthy but even then if it didn’t do it for me i don’t think it would help anyone’s actually damaged and brittle hair. Can’t say I’d reach for this in my hair routine, it’s just not giving the results it should and especially not for the price it’s selling for.

Originaly posted on  influenster.com

Reply from Consumer Care Center 09/09/2025

Thank you for your feedback. We're glad you love the scent and bottle design. We're truly sorry to hear this product didn't meet your expectations, especially regarding its drying effect and lack of frizz reduction for your hair type. We understand your disappointment, particularly given your past positive experiences with our brand and the product's price point. Your detailed insights are very important to us as we continuously strive to improve our offerings. We appreciate you sharing your honest experience.

ayeefilthy_2571

5

1.757106908E12 05/09/2025

Quality product

[This review was collected as part of a promotion.] My hair feels so healthy after I started using this product! I curl my hair often and was missing a good heat protectant. I love that this product smells good, is lightweight. And has seemed to help with breakage!

Originaly posted on  influenster.com

almaadee__8191

5

1.757003408E12 04/09/2025

Better than my usual protectant

[This review was collected as part of a promotion.] My staple heat protectant isn’t in this type of spray, so I was very curious to try this product that was sent to me for review purposes. I frequently see this on TikTok, to make it short I am now adding a new staple product to my rotation. The price range is fine by me, I don’t mind spending on products that I think are worth it. This is worth it. I can actually tell a difference in heat protectant vs the other product I use. I’m seeing less damage on my tips. Usually when I use heat every single day for like a month, my tips(only the tips) feel a bit crunchy. Once I give them some love and rest, back to normal. I haven’t felt that same crunchiness since using this new product. Another plus..I am sensitive to smells, however this product smells delicious and actually covers up the smell of no wash days lol. I can understand the hype now. I’m glad I was able to try it before purchasing myself.

Originaly posted on  influenster.com

Dulcerod

5

1.756913407E12 03/09/2025

LOVE IT

[This review was collected as part of a promotion.] Love this heat protectant so much it’s great for detangling leaves your hair so soft and smells amazing !!!!

Originaly posted on  kerastase-usa.com

hollandp_2770

5

1.756886409E12 03/09/2025

I love this stuff

[This review was collected as part of a promotion.] I literally LOVE this stuff!!! The smell of it is just so dang good, I can’t get enough of it. I’ve been using this for about 3 weeks now and so far so good. My hair is so easy to brush after spraying this on my hair before blow drying. It helps keep my little new growth crazy stubborn stray hairs down which is HARD for a product to get done! I recommend this product to anyone looking to help strengthen, smell good, dry damaged hair.

Originaly posted on  influenster.com

nikkic38_2946

5

1.756913407E12 03/09/2025

Great product

[This review was collected as part of a promotion.] This protectant spray is excellent! It smells great and works very well with a curling iron! Would recommend and would purchase in the future. Received free for my honest feedback.

Originaly posted on  influenster.com

jpw_957

4

1.756783803E12 01/09/2025

Soft and nourished hair

[This review was collected as part of a promotion.] A lovely gentle scented hair protectant that leaves my hair nourished and soft. I only blow dry my hair sometimes but I definitely notice the difference. I would have preferred a pump head over a spray nozzle but it’s great otherwise.

Originaly posted on  influenster.com

nazubazu_6548

4

1.756783803E12 01/09/2025

very good product

[This review was collected as part of a promotion.] i regularly use the dyson airwrap so i have been testing this product alongside it - i’ve noticed that the product works well, the scent is pleasant and my hair feels softer upon using it. i can’t say much for how effective it is for heat damage but it has a nice consistency and texture. i’d recommend.

Originaly posted on  influenster.com

Haydee

4

1.756816208E12 02/09/2025

Smooth Hair

[This review was collected as part of a promotion.] Makes my hair feel very smooth and smells delicious!!

Originaly posted on  kerastase-usa.com

abigailmichelle_8488

5

1.756744207E12 01/09/2025

Effective and Smells Nice

[This review was collected as part of a promotion.] I was really excited to try this as I am already a fan of the brand. I usually don’t use heat on my hair because I’m trying to limit the damage. However, this was effective as a protectant and prevented frizzing. It also made my hair shiny. It smells good, too!

Originaly posted on  influenster.com

lauragsweet_9785

5

1.756654207E12 31/08/2025

The best of the best!

[This review was collected as part of a promotion.] I used this product years ago and honestly don’t know why I quit buying it. When Influenster sent it to me to review, my love was rekindled immediately! Though I don’t heat treat more than once or twice a week, I can feel the difference in my hair’s softness and texture.

Originaly posted on  influenster.com

dianam937_5053

5

1.756599306E12 30/08/2025

Beauty Staple!

[This review was collected as part of a promotion.] Love this protective thermal product! It smells good but also very light and not overpowering. Love the pink packaging and size. Great value. I use it as my only product on vlean hair and it helps with frizz all day! I don’t even have to use any other hair product.

Originaly posted on  influenster.com

nicolem245_4206

5

1.756515605E12 29/08/2025

Amazing blowout/styling

[This review was collected as part of a promotion.] Always looking for a heat protectant that also doubles up with other benefits. This spray is so easy because you just spray on damp hair and it makes your hair so smooth and smells amazing. It also makes my hair super soft and helps the blowout/styling stay smooth for a few days.

Originaly posted on  influenster.com

tinaj114_177

5

1.756506624E12 29/08/2025

Stronger, Softer Hair That Survives the Heat!!

[This review was collected as part of a promotion.] I’ve been using the Genesis Defense Thermique Heat Protecting Spray from Kérastase, and it has made a noticeable difference in my hair. The spray is really lightweight, so it doesn’t make my hair greasy or heavy. I usually apply it before blow-drying or straightening, and it gives my hair a smooth, silky finish with less frizz that actually lasts all day. What I like most is that it protects my hair from heat styling while also keeping it nourished and shiny. My hair feels stronger, looks healthier, and I’ve noticed fewer split ends and less breakage when brushing. It also helps keep my hair conditioned and soft, which is a big plus since I style it often. Overall, it’s an easy step in my routine that makes a big difference—especially if you want to keep your hair protected, smooth, and less prone to damage from daily styling.

Originaly posted on  influenster.com

otulai_1160

5

1.756506624E12 29/08/2025

Healthy hair

[This review was collected as part of a promotion.] Kérastase Genesis Défense Thermique is my new go-to heat protectant—lightweight, smells amazing, and leaves my hair smooth, shiny, and frizz-free while protecting up to 450°F. A bit pricey, but worth it for strong, healthy hair.

Originaly posted on  influenster.com

Barb516

1

1.756502568E12 29/08/2025

Not a fan of this whole line

Smells weird, not very hydrating, and my blowout was weird afterwards. Not very happy with this whole product line, and will not be repurchasing.

Originaly posted on  kerastase-usa.com

Reply from Consumer Care Center 29/08/2025

Hi there! We're very sorry to learn that Genesis Defense Thermique Heat Protecting Spray was disappointing for you, especially concerning its scent, hydration, and how it affected your blowout. We understand your frustration and value your feedback about this product line. You might consider trying Blond Absolu Cicaplasme Thermique Heat Protecting Cream for hydrating and strengthening blonde hair instead. We hope Blond Absolu will better suit your hair concerns and preferences. https://tinyurl.com/yxug46pn

parrishe_4891

5

1.756506624E12 29/08/2025

Leaves my hair soft and smooth

[This review was collected as part of a promotion.] I have really enjoyed using this heat protecting spray. I have naturally curly hair so it takes some heat abuse from time to time when I decide to straighten or blow-dry it. This spray is very easy to use and seems to evenly distribute a fine mist over my hair. This spray has a nice scent that isn't too overpowering for me. It feels very lightweight, even when I feel like I've used a lot. After using my heat source, where it be my hairdryer or straightener, my hair is left soft and smooth with a bit of shine. I'm really enjoying this product. This has quickly become my go-to spray to help protect my hair from harmful heat!

Originaly posted on  influenster.com

Anonymous

5

1.756489508E12 29/08/2025

Demasiado suave y mucho brillo

Me encanta, deja mi pelo extremadamente suave y saludable.

Originaly posted on  kerastase-usa.com

    Defense Thermique 150ml

    Kerastase - Genesis

    Product code : 3474636857975

    Anti Hair-fall Fortifying blow-dry fluid for weakened hair, prone to falling due to breakage. Provides anti-breakage action and heat protection up to 220°C. Ensures optimal hydration without frizz.

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