One thing I will say about my hair is that it's always a frizzy mess. Mercy! Ever since I was wee. And look, sometimes frizzy can look cool and effortless on certain hair types. On mine? It just looks… feral. Like I've just rolled out of bed and said, "f**k it."

Listen, my boufy, frizzy hair has always been an ongoing battle. Pretty sure the first product I ever bought for my hair was John Frieda's Frizz Ease when I was 13 years old.

Watch: Is this $185 hairbrush worth the price tag? Post continues below.

I also had some form of keratin yonks ago — and it smelled like an old banana and made my hair look weirdly piece-y and oily for about a month.

You see, my hair is naturally quite curly, but I always style it straight or wavy to try to avoid The Frizz.

For this reason, I use all of the hair products. Specifically, hair oil. It has become an absolute staple in my post-styling routine. I only wish I could go back in time and pop some into my school-day routine, rather than using my dad's hair gel to try smooth it down (omg blesssss).

Anyway, back to the hair oil. Have literally tried every single one on the market.

In fact, anything with the words 'sleek', 'shiny' or 'smooth' — I've tried it.

So, you can imagine my delight when Garnier Fructis released the new Sleek & Stay range for frizzy, dry hair.

Hoo-boy.

What is Garnier Fructis Keratin Sleek & Stay Serum?

More specifically, let's talk about the heat-activated serum. It retails for $25, but psst… I've frequently seen it on sale for as low as $12, and you can grab it right on your regular supermarket run at Coles.

Here's what it looks like:

How did you go with it?

Because it's a heat-activated formula, the magic happens when you apply it to damp hair before you bring out the blow-dryer or straightener.

You shake it to 'activate' the formula, and I applied about two pumps through my mid-lengths to ends, aiming for even distribution without weighing down my roots. because NOTHING sucks more than washing your hair, applying product and realising that it's just made your hair look like a bag of grease. THE WORST.

The formula itself is lightweight, has a lovely scent and seems to absorb quickly without feeling heavy or greasy. In terms of frizz control, my hair lasted pretty well through a rainy day, and it gave my hair a natural, shiny gloss.

Here's what my hair looked like without the serum post-wash on the left and then WITH the serum post-wash on the right (same styling routine!):

Thoughts? Feelings?

The verdict.

I've been seriously contemplating booking in for a proper, professional salon keratin treatment. But it's spendy, and I don't know if I can justify splashing out that kind of money on my hair.

So, does a budget supermarket serum replace a multi-hundred-dollar salon treatment?

To be honest, the results aren't the same as a professional treatment — while it kept my hair somewhat frizz-free (I used it in conjunction with the shampoo, conditioner and mask in the range), it's not going to permanently alter your hair texture like a chemical service does.

But! As an affordable, daily add-on to your existing routine? It absolutely holds its own.

Because when you've spent hundreds of dollars over the years on high-end salon formulas, you don't necessarily expect a supermarket product to do the heavy lifting. But this stuff surprised me.

It didn't leave a weird chemical smell, and it didn't make my hair look like an oil slick by day two. Instead, it just made everything more manageable and even helped smooth down the post-partum flyaways.

So! If you're trying to stretch out the time between salon visits or just looking for a solid frizz-fighter that won't blow the budget —it's well worth the try.

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