From clever leave-in conditioners to bond-repair treatments that rival Olaplex, the industry is bursting with innovative hair products which promise to stitch split ends back together, keep frizz on lockdown and make hair appear impossibly glossy. But in my honest opinion, you can’t beat a simple hair oil.

Easily slotted into any haircare routine (whatever your hair type or texture), hair oils can be used on towel-dried hair to promote shine and boost moisture and manageability, or on dry hair to help with styling. There are plenty to choose from. Beauty brands love nourishing argan oil in particular, but castor oil, avocado oil and coconut oil are just a handful that we can’t get enough of for promoting growth, softness and gloss. As a beauty editor, I’m lucky to try hundreds of hair products which all pledge transformative properties. While there are so many brilliant buys out there, I always come back to hair oil, and there’s one product I will always suggest to friends, family or pretty much anyone who asks for my top hair recommendation.

Enter: Kérastase Elixir Ultime L’Original Hair Oil.

Leave-in hair oil is nothing new. In fact, this particular hair oil has been a favourite for years. You might have spotted the iconic gold bottle on your hairdresser’s workstation or noticed boxes of the stuff stacked in the window of your favourite salon. Experts swear by it and there’s a reason why it pops up everywhere: It really is as good as everyone says it is.

What’s in Kérastase Elixir Ultime L’Original Hair Oil?

The star ingredients in the product are argania spinosa kernel oil (or argan oil), cyclopentasiloxane (a safe, hair-friendly silicone which leaves lengths ultra soft, shiny and frizz-free, and doubles up as heat protection) and a megamix of other plant-based oils such as corn oil and pracaxi seed oil, known for strengthening brittle hair strands.

The texture feels more like a silky serum than an oil, which can be thick and sticky, separating hair or making it look greasy. As a result, it works across the board for all hair types, including fine hair. Experts say that argan oil, in particular, is one of the best oils for natural hair, improving elasticity and making strands soft. It’s especially great for curly hair, which tends to require more moisture. (There are some great YouTube reviews, too.)

What are the benefits of Kérastase Elixir Ultime L’Original Hair Oil?

My hair is thick, naturally wavy and has been bleached and dyed multiple times over the past couple of years. Plus, I’m due a much-needed haircut and I straighten my hair most days. It’s safe to say I need as much moisture as possible to minimise the appearance of split ends and my perpetually frizzy roots. I’m impatient, too, and anything that cuts styling time in half gets my vote. Elixir Ultime does all of that in just one tiny pump.

A pea-sized amount (raked through towel-dried hair and concentrated mainly on the ends) is all it takes to make my hair look like it has been professionally washed and styled, even if I’ve just given it a rough-dry and a very speedy once-over with my trusty ghd Platinum+ Hair Straightener, £160. I can usually tell a product is excellent when I don’t use it. Testing shiny new launches means I often have to shelve Elixir Ultime for a couple of weeks at a time — and I notice a big difference in the quality of my hair.

While I don’t have any gripes, I have to acknowledge the price tag. At £45.80 (£36.64 on sale), this luxury oil is almost quadruple the price of many hair oils the high street has to offer. That said, a little goes a very long way and the 100ml bottle is almost twice the size of some drugstore versions. Applied through damp lengths two to three times a week, mine lasts a good eight months, making it an investment beauty buy.

Personally, I think the original Elixir Ultime is the best (the woody, musky smell has me sold) but the rose version is just as good. In fact, the product line has recently expanded so there is an oil suited to a wider range of hair needs, such as bleached hair, which may be overprocessed or damaged (Blond Absolu Huile Cicaextreme Oil, £41.22) and curly or very thick hair (Huile Discipline Oleo-Relax, £41.22).

If you’re looking for cheaper alternatives with similar effects, VO5 Invisibly Light Hair Oil, £3.25, boasts Kérastase’s top ingredient: cyclopentasiloxane. Don’t let the complicated name put you off. While we’ve been made to fear silicones for clogging the scalp or “coating” hair, they are entirely safe to use and it’s hard to deny how well they make hair gleam. As silicone transfers heat slowly, it also acts as a great heat protectant, shielding hair from hairdryers, straighteners and tongs. Silicones can easily be washed out with the right shampoo. This oil contains argan kernel oil, too, which moisturises both hair and scalp and protects strands from environmental aggressors such as cold weather and pollution.

Also try Pantene Pro-V Keratin Protect Hair Oil Repair & Protect, £7.99, and OGX Renewing+ Argan Oil of Morocco Penetrating Oil, £5.99. Both are R29 favourites with similar glossy hair ingredients.

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