Bad news: Those bond-building treatments could be ruining your hair.

If you've ever used a bond-building treatment (hello, Olaplex devotees), only to find your hair feeling more damaged than ever, you're not alone.

In fact, on a recent episode of You Beauty, hosts Leigh Campbell and Kelly McCarren tackled this exact dilemma after a listener named Matilda asked why her split ends seemed to be getting worse after using bond-building products.

The answer? Well, it's all about balance, boo.

Watch: Speaking of hair… here's your foolproof guide to chic and easy beach waves. Post continues below.

"I love this question. I go through that at home myself," said Leigh.

And SAME. Why are these expensive bond-building products making our hair feel like literal straw?

"Think of it like your diet," Leigh explained. "Say all you do is eat protein and you don't have the fibre... you kind of get constipated. It's kind of like that for your hair."

An oddly perfect analogy, no?

Want to listen to the full episode? Check it out below.

Y'see, while bond-building treatments (think Olaplex, K18, and anything with 'plex' in the name) work to strengthen your hair's cortex and cuticle, they're essentially just pumping your strands full of protein. Without balancing it out with hydration (the 'fibre' in this scenario), your hair can end up feeling dry and brittle.

As Leigh put it: "It's like rendering a wall and then just leaving it all rendered. You've got to then sand it and paint it." The hydration part? That's your paint.

So, do you actually need bond-building treatments?

Well, it depends on your hair type and how much damage you're dealing with — because contrary to what you might believe, not all hair types really need expensive bond-building treatments.

As a general rule of thumb, if you have virgin hair (never coloured your hair) and rarely heat style — you probably don't need it.

Bleached blonde? You'll benefit from bond-builders — but use them sparingly.

Damaged ends only? Just apply it to the affected areas — you probably don't need to use it all over.

How often should you use bond-building treatments?

When it comes to how often you actually need to use bond-building treatments in your haircare routine, both hosts agree that less is more.

"Once a week-ish, maybe once every 10 days," Kelly suggested, noting that she uses them more frequently during summer when she's swimming more.

Leigh added that for her darker, shorter hair, even once a week would be too much. (She also said she likes to just use it on her ends — not all over).

The key? Follow. The. Instructions.

"When I first started using Olaplex, I was like, 'More! And leave it in for longer!' and it just wasn't what you're supposed to do," Leigh admitted.

What are the best bond-building products?

While we all know and love Olaplex, if you're looking for some other great options, Leigh recommended the Toni & Guy Strength Plex Bond Repair range. (And yes, you can grab it from Woolies!).

"I love the shampoo, conditioner and mask," she shared.

She also rates Kerasilk Strengthening Bond Builder, $50, sharing that it's great as a leave-in styling product (but again — use it sparingly!).

If you're looking for a luxury buy, Kelly's fave is the popular K18 Leave-In Molecular Repair Mask, $99.95 — which obviously comes with a hefty price tag.

Her hot tip? "Get the 15ml travel size from Sephora or Adore Beauty first. It's a great way to trial it because it's honestly 50/50 — people either love it or just don't get it."

Smart thinking.

The most important thing you're probably forgetting.

Okay, but here's the real tea: bond-building treatments are only half the story. You need to balance out all that protein with moisture.

"Just because you've done the protein part, the 'plex' part, the bond part… you [still] need the 'fibre,'" Leigh explained.

"Have the fibre, sand that wall down and paint it by using really beautiful, juicy and nourishing moisturising conditioner and masks."

So if your hair's feeling more hay-like than silky and lovely after using bond builders, try:

• reducing how often you use them

• only applying to damaged areas

• following the instructions exactly (we know it's boring, but trust us)

• using hydrating masks and conditioners between treatments.

Because sometimes, as with most things in life, less really is more. Even when it comes to those fancy bond-building treatments.

Are you a fan of bond-building treatments? What are your favourite picks, and how often do you use them? Share with us in the comment section below.

Feature image: Instagram: @olaplex; @k18_australia; @beautyandthespender.