'I tried a $20 haircare hack that promises to fix an oily, flaky scalp. Now I'm converted.'

I'm at a point in my life where I just don't care about my digital footprint anymore, and I'll admit to anything if it means it'll make for a good story. Which is why, I'm about to delve into the toxic relationship I have with my scalp.

Yep, you heard me. My scalp is a raging pain. It's oily, flaky, and over the years, I've tried everything to keep it under control, but to be honest, not much has worked.

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So, when I came across The Ordinary's Glycolic Acid TikTok hack, which claimed to keep dandruff and greasiness at bay, I thought, "Eh, why not try it? It can't make matters worse, right?"

Now, if you're not like me and actually go outside and see the sun instead of rotting indoors, doomscrolling all day, then you probably have zero clue of what I'm talking about.

@echristina13 Please do your own research and this does make your scalp sensitive to the sun! I have a coconut allergy so products are hard for me to find that accommodate my allergies. #coconutfreeproducts #dandruff #dandruffsolution #dryscalpremedy #dryscalp #scalpcare #hairtips #glycolicacid #theordinary #scalphealth #dandrufftreatment ♬ original sound - joker

Allow me to explain.

Dandruff is essentially a build-up of dead skin, so when you apply glycolic acid - a chemical exfoliant - to the roots of your hair, it works as a non-abrasive scrub and removes the layers of particles sitting there for who knows how long (pretty sure mine have been on my head since 1995).

Can you use any glycolic acid? Or does it have to be from The Ordinary?

So, the short answer is: Yes, you can use any glycolic, but there are two reasons The Ordinary's version is so special.

1. It boasts seven per cent glycolic acid, which, considering it's meant to be used on the face, is really intense. For the scalp, however, it's the perfect strength and rumour has it that it works phenomenally on cracked feet too.

2. The nozzle makes it easy to get into every nook and cranny on your scalp.

The Ordinary Glycolic Acid 7% Toning Solution Treatment, $20.50.

Image: The Orindary, MYER.

How do you use glycolic acid on the scalp? And what are the benefits?

According to TikTok, glycolic acid will give you the best results if applied to the scalp thirty minutes before jumping in the shower. After half an hour, wash your hair as normal, and you should be left with a flake-free scalp that doesn't turn oily after someone glances in its direction.

It's important though to monitor how frequently you're applying it, with Trichologist Carolyn Evans-Frost saying to not overdo it.

"I would not suggest more than once every two weeks. When removing any type of scalp or skin build-up, the purpose is to safely remove or exfoliate, then help, or allow the skin underneath to heal," Evans-Frost tells Mamamia.

As for its benefits, there seems to be quite a few.

"Glycolic acid has been used in cosmetics and hair care products since the 1800s because of its ability to penetrate deep into the layers of the skin epidermis and the hair fibres," says Evans-Frost.

"It can help increase cell turnover, creating an exfoliating effect and boost hydration on the scalp, which will help prevent more dandruff from forming."

Here's my review.

Get ready, because we're about to get up close and personal.

I've tried this every fortnight for the last two months, so I like to think my review holds some weight to it. Before I added glycolic acid to my routine, my scalp was desperate for exfoliation. I had flakes attached to my jet-black strands (which just made them even more prominent) and my hair would get oily after one day. Yes, ONE DAY.

My freshly washed hair after rinsing out the glycolic acid. Image: Supplied.

I follow the instructions and leave the toner on for 30 minutes, before jumping in the shower and double cleansing my hair. I first go in with a shampoo from root to tip, and then after washing that out, I shampoo the scalp again and apply conditioner to my ends.

It's important to wash every last bit of product out from your hair - if you think you're done, then rinse for another minute. Product residue is also to blame for scalp irritation and can make your hair oilier faster. The first time I used it, my scalp felt much cleaner and more refreshed, however, my dandruff didn't fully go away and my hair got greasy at the two-day mark instead of one.

What my hair used to look like after four days before using glycolic acid and what it looks like now after four days. Image: Supplied.

But now, two months later, I can safely say that the roots of my hair have done a complete 180. Not only is my dandruff close to non-existent (it still pops up here and there), but I can go four days without washing my hair. I also feel as if the health of my hair has improved, and that could be because it's so much cleaner than it used to be.

That makes me sound nasty and I promise I'm not.

Are there any cons to using glycolic acid on the scalp?

Yes, but not because of the product itself. Glycolic acid is a great ingredient to use on the scalp, however, overusing it can cause serious irritation. Remember, it is an acid after all, and it's a potent ingredient.

"Long-term use can dehydrate the scalp exacerbating the dryness further. It can also thin the skin over time - It is a chemical exfoliator after all," says Evans-Frost.

"Glycolic acid has no endpoint, allowing it to travel deeper than intended if left on the skin for too long. It also has a small molecular size and can absorb quickly, causing the skin to peel unevenly. 

"And be careful not to use glycolic acid 10 per cent or over unless under professional guidance."

I followed Evans-Frost's advice and used it once every two weeks, and I found that was sufficient to keep dryness and greasiness at bay.

So, would I recommend glycolic acid to help with an oily scalp and dandruff? Absolutely. Use it at your discretion, however, for me, it's worked brilliantly and unless some other miracle product pops up on the market, I won't be stopping anytime soon. 

Have you tried this hack before? Tell us know it worked for you in the comment section below.

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Feature Image: Supplied.