Kérastase Elixir Ultime Oil Is a Heat-Styling Essential

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Kérastase Elixir Ultime Hydrating Hair Oil Serum

kerastase elixir ultime

Kerastase / Design by Cristina Cianci

Kérastase’s Elixir Ultime Hydrating Hair Oil Serum

What We Like
  • Adds shine without weighing it down

  • Protects fragile curls from heat damage

  • Smooths extra-dry, crunchy ends

What We Don't Like
  • High price point

  • Hair can feel greasy if too much is used

Kérastase’s Elixir Ultime Hydrating Hair Oil Serum is a hair oil that checks every box for all hair types—including the curliest, coiliest strands. Whether you want to use the oil as a heat protectant, a treatment, or as a serum to boost shine, Elixir Ultime has you covered.


Kérastase Elixir Ultime Hydrating Hair Oil Serum

kerastase elixir ultime

Kerastase / Design by Cristina Cianci

As a curly girl, I enjoy caring for my super coily strands. But as much I enjoy a good twist out, a couple of times a year—particularly, when I’m prepping for a protective style—I give my hair a blow dry and style it with a flat iron. In search of a new heat protectant for these moments, I got my hands on the Kérastase’s Elixir Ultime Hydrating Hair Oil Serum. I've heard great things about this multi-use formula, but wondered—would it work for my curls? Read on for my honest thoughts below.

Best for: All hair types

Uses: Hydration, shine, preventing frizz and breakage, heat protection 

Potential allergens: Linalool, Alpha-Isomethyl Ionone, Limonene, Coumarin, Benzyl Alcohol, Parfum/Fragrance 

Active ingredients: Marula Oil, Camellia Oil, Argan Oil 

Clean?: Yes

Price: $44-$51 

About the brand: Kérastase is an accessible luxury haircare brand that focuses on creating innovative products that yield salon-like results. Backed by science and plenty of research, Kérastase aims to provide customers with a personalized, lush experience right at home.

About My Hair: Low porosity, 4A curls

While it took some time for me to figure out how to best care for my hair, I appreciate my curls. My hair has low porosity, so it takes a really long time to absorb water and moisture from products. This also makes my twists take two days to dry. For the past few years, I’ve been rotating between Melanin Haircare, Camille Rose Naturals, and Shea Moisture products for just about everything: shampoo, deep conditioner, leave-in, and styling cream. The products from these brands make my hair feel moisturized without being weighed down. It's the result that I look for in products, and I hoped this hair oil could create it.

beauty writer khera alexander

Khera Alexander

When I put heat on my hair, I apply a leave-in conditioner (I've been using the Shea Moisture Sugarcane Extract & Meadowfoam Seed Silicone Free Miracle Styler Leave-In Treatment) first, then layer a heat protectant on top of it. After spritzing the leave-in onto my damp, I applied one pump of the Elixir Ultime to each section.

The Feel: Lightweight and silky, but not greasy

When I pumped the Elixir Ultime oil into my hand, it had a beautiful texture. It's thin, rich, and has slip without feeling greasy. After applying one pump of oil to each section of my hair, I used my blow dryer on the cool setting and ran my fingers through my hair to get a feel for how the product was working. My hair had movement, felt soft, and it didn’t feel dry at all. This was a pleasant surprise, because other heat protectants I’ve used have made my hair feel dry and crunchy. 

There was a slight residue on my hands after I ran them through my hair, but that was more me than the product. I might have applied too much of it on my lengths and could have gotten away with using half a pump instead.) When I was getting ready to flat iron my hair, I applied one more pump to my ends. It was a reflex—I knew I didn’t need any additional product, but my ends are so dry that it's become a reflex to apply more product to it.

The Results: Smoothed, hydrated, shiny hair.

khera alexander kerastase ultime

Khera Alexander

After I finished styling my hair, my hair was sleek, shiny, and still felt nourished without feeling heavy, stiff, or weighed down. The Elixir Ultime coated my hair well, especially my ends. Usually, I’d have to use a small toothed comb to smooth out a particular section of my ends first, flat iron that section, comb the ends out again, and flat iron it again, repeating this process up to four times. I only had to go over my ends twice when I used Elixir Ultime, which was exciting. As the day progressed, my hair continued to have great movement and shine. 

Similar to my twist outs, second day hair is always better than first day hair. The residue I mentioned having on my hands above disappeared when I ran my fingers through it, but the shine remained. I kept my hair straight for a little over a week to make the most of it and used half a pea-sized amount of the Elixir Ultime a few more times to add shine. Having a couple of layers of oil on my hair still didn’t make it feel weighed down. Toward the end of the week, I didn’t have as much movement in my hair as I did the first half, which was to be expected. In between workouts, showers, and not putting any additional heat on my hair, I knew it wasn’t going to look and feel like it did the first day I styled it.

What stood out during this experiment was my hair and rough ends felt more hydrated and smooth throughout the week after using this product, than it has after I used other heat-styling products. With other heat protectants, my hair usually feels crunchy after two or three days, and I’d have to put in a lot of work to flatten my ends. Based on these two things alone, Elixir Ultime really impressed me.

The Price: Worth the splurge

Kérastase’s Elixir Ultime retails for around $44-$51 for 100ml—that’s a pretty hefty price tag for a hair oil (considering they can be sold for as low as $3), but the cost is justifiable if you are looking for a hybrid heat-protectant and hair oil. I could see myself investing in this product again. After all, with all of its uses, it would pay for itself over time.

Similar Products: You have options

John Frieda Frizz Ease Extra Strength Serum: A really rich serum that coats hair and protects it from heat styling tools, the John Frieda Frizz Ease Extra Strength Serum ($9) is a drugstore product that can be compared to the Elixir Ultime—it just doesn’t have as many uses. With a blend of argan, coconut, and moringa oils, this serum can be used on wet or dry hair to tame frizz and resist humidity, but may weigh down really fine hair.

Cantu Shea Butter Thermal Shield Heat Protectant: Another wallet-friendly option, the Cantu Shea Butter Thermal Shield Heat Protectant ($7) will hydrate your hair while protecting it from heat and humidity. Reducing frizz and flyaways as well, this product is a great option if you need a straightforward heat protectant in a lightweight spray.

Final Verdict

The Elixir Ultime Oil from Kérastase surpassed my expectations as an oil and heat protectant. Completely smoothing over my frizzy ends and making styling my hair with heat tools a much easier process, this expensive oil is worth the investment, especially if you use oils in your routine in different ways—Elixir Ultime also works as an oil for touch ups and treatments.


  • Product Name Elixir Ultime Hydrating Hair Oil Serum
  • Product Brand Kérastase
  • Price $52.00
  • Weight 3.4 oz.
  • Full Ingredients List Cyclopentasiloxane, Dimethiconol, Zea Mays, Corn Germ Oil, Argania Spinosa Oil, Argania Spinosa Kernel Oil, Sclerocarya / Birrea Seed Oil, Camellia Oleifera Seed Oil, Caprylic/Capric Triglyceride, Linalool, Pentaclethra Macroloba Seed Oil, Phyllanthus Emblica Fruit Extract, Alpha-Isomethyl Ionone, Limonene, Coumarin, Benzyl Alcohol, Tocopherol, Parfum/Fragrance.

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