Keratin vs Nanoplasty vs Brazilian Blowout, Which Smoothing Treatment Is Right for You?
The Melbourne Summer Frizz Problem
Every January and February the same conversation happens at the Kohort basin. A client comes in, Yarra side of Richmond, been caught in three thunderstorms in a week, hair is a halo of frizz and she just wants it to behave. She's read something about keratin, heard something about nanoplasty, seen a TikTok about Brazilian blowouts, and isn't sure which one is right for her.
They are not the same treatment. They produce different finishes, use different chemistry, last different amounts of time, and carry different health considerations. Picking the wrong one is how you end up with poker-straight hair when you wanted loose waves, or limp wet-noodle hair when you wanted structure, or a $450 treatment that washes out in eight weeks.
This guide walks through what each one actually is, who it suits, what it costs in Melbourne, and what to watch for when you book. I've been doing smoothing treatments at Kohort for years, and the same mistakes come up again and again. Let's save you from making them.
The Straight Answer
| Treatment | Chemistry | Finish | Works on | How long it lasts | Approx cost (Melbourne) | Formaldehyde? | Downtime |
|---|---|---|---|---|---|---|---|
| Keratin (Bhave) | Keratin-based smoothing, formaldehyde-free formula | Smooths frizz, reduces volume 40 to 60%, keeps natural movement | Wavy, frizzy, thick, medium-coarse | 3 to 5 months | $250 to $500 | No (Bhave is formaldehyde-free) | Wash hair 24 to 48 hrs after |
| Brazilian Blowout | Acid-based with keratin, original formulas contained formaldehyde | Sleeker, glossier, more dramatic straightening | Wavy to curly, frizzy | 3 to 4 months | $280 to $500 | Classic formulas yes, newer formulas varying levels | Wash hair immediately same day |
| Nanoplasty | Amino acid (not keratin), low heat, botox-style molecular repair | Reduces frizz without straightening, nourishes, glossy natural movement | Fine, fragile, already-damaged, colour-treated | 2 to 4 months | $300 to $550 | No | Wash hair 48 to 72 hrs after |
| Cezanne | Keratin-based, low formaldehyde derivative, botanical | Smooth, glossy, retains curl | Wavy, colour-treated | 3 to 5 months | $350 to $600 | Contains methylene glycol (releases formaldehyde when heated) but below US ceiling | Wash 24 to 72 hrs after |
The one-sentence test: keratin smooths and softens, Brazilian blowouts straighten hard, nanoplasty repairs and tames. Everything else is a variation on those three approaches.
Keratin Smoothing, What It Actually Does
Keratin is a protein. Your hair is made of it. Keratin smoothing treatments take a version of that protein, dissolve it in a carrier solution, coat it onto your hair strand, then use flat-iron heat to bond it to the cuticle. The result is a smoother, sleeker surface, less friction when hair rubs against itself, and a significant drop in frizz.
At Kohort we use Bhave Keratin Smoothing, which is formaldehyde-free. Bhave's formula uses a blend of keratin and active botanicals, not the traditional methylene glycol chemistry that released formaldehyde when heated. This is the part of the conversation most clients don't know to ask about.
What keratin smoothing does for your hair
- Cuts daily blow-dry time roughly in half.
- Reduces the frizz halo you get in Melbourne humidity.
- Keeps natural wave pattern (your curl type is still there, just softer).
- Adds visible gloss and light reflection.
- Makes colour-treated blonde sit more evenly.
- Lets you air-dry without looking frizzy.
What keratin smoothing doesn't do
- It does not make curly hair straight. A 3b to 4a curl pattern stays curly, just tamer.
- It does not last forever. Four to five months, then it fades out gradually.
- It does not damage hair when applied correctly. But badly applied keratin on over-processed hair can tip fragile hair into breakage.
Brazilian Blowout, The Original, And The Controversy
The Brazilian blowout is where this whole category started. The original formulas from the mid-2000s contained formaldehyde (or chemical precursors that release formaldehyde when heated to over 200°C). That is why there was a class-action settlement in the United States in 2010, and why the TGA and regulators in multiple countries tightened rules on the product.
Modern Brazilian blowouts vary. Some brands have genuinely reformulated to formaldehyde-free. Others still use methylene glycol, formalin, or formaldehyde-releasing aldehydes and market themselves as "formaldehyde-free" because the ingredient isn't listed under that exact name. This is where you need to ask your stylist direct questions.
What a Brazilian blowout looks like in the chair
The chemistry is acid-based. The product is painted on section by section, combed through, then heat-sealed with a flat iron at around 230°C. The finish is glossier, flatter, and straighter than a keratin smoothing. Your curl pattern is significantly reduced.
Why some clients still choose it
- The finish is sleeker than keratin smoothing for clients with very resistant frizz.
- It works fast in humid climates like coastal Queensland or St Kilda beach-adjacent hair.
- It holds up under intensive training (marathon running, Pilates, daily gym) better than some keratin formulas.
Why we don't offer classic Brazilian blowouts at Kohort
We made a call a few years ago to offer only formaldehyde-free smoothing. The clients coming through our Richmond studio skew health-conscious, a lot are pregnant or trying for a baby, and a lot are working in Cremorne tech offices where they don't want to spend three hours breathing in flat-iron vapour that smells chemical. Bhave gives us a finish that's comparable to a modern Brazilian blowout without the indoor air quality concerns.
Nanoplasty, The One Your Hair Actually Needs If It's Already Damaged
Nanoplasty (sometimes called "hair botox" or "nanokeratin") is the youngest of the three. It is not a keratin treatment. The active ingredients are amino acids and a botanical complex, applied at lower heat than a keratin or Brazilian, and designed to reconstruct the hair fibre from the inside out rather than just smoothing the surface.
Think of it like this: keratin smoothing is a shell around the hair, nanoplasty is a repair from the core. That's why nanoplasty is the usual pick for:
- Fine hair that goes flat under a traditional keratin.
- Over-processed blondes whose ends are already fragile.
- Colour-corrected hair still in rebuild mode.
- Clients who want frizz control without any straightening effect.
What the process feels like
Shampoo, mask-like product applied, left to sit, gently dried in, flat-iron sealed at a lower temperature than keratin (around 190°C versus 230°C), rinsed. Shorter downtime too, most clients can wash within 48 hours, and some formulas allow washing within 24.
The finish is shinier and bouncier rather than sleeker. If you want your curl or wave back, nanoplasty keeps it. If you want straight, this is the wrong treatment.
How To Choose, A Decision Framework
Walk through these questions honestly:
1. What's your curl type? If you're 1 to 2a (straight to loose wave), a full keratin or Brazilian is overkill. Nanoplasty or a lighter keratin finish serves you better. If you're 2b to 3a (wavy to loose curly), keratin smoothing is usually the sweet spot. If you're 3b and beyond (tight curl), be cautious, smoothing a tight curl often gives a result you don't actually want.
2. Has your hair been heavily coloured or bleached? Bleached blondes and colour-corrected hair should default to nanoplasty. A keratin on top of compromised hair can work, but it is riskier and the result is shorter-lived.
3. What is your wash frequency? Smoothing treatments last longer on clients who wash two to three times a week than clients who wash daily.
4. What finish are you actually after? If the answer is "natural movement but less frizz," pick keratin or nanoplasty. If the answer is "stick-straight and sleek," a Brazilian is the closer match, but be ready to interrogate your stylist about the formula.
5. Are you pregnant, trying to conceive, or breastfeeding? Don't do any traditional keratin or Brazilian. Bhave is formaldehyde-free and is the only formula we'll do on clients in those circumstances, and even then, many stylists prefer to wait till after. Ask your GP.
Melbourne-Specific Considerations
Melbourne's weather does things to hair that clients who moved here from drier cities don't expect. Summer humidity along the Yarra through Richmond, Abbotsford and Burnley sits in the 60 to 80% range on bad days. That's when natural wavy hair turns into a frizz halo and the smoothing-treatment conversation begins in earnest.
The clients who get the best mileage out of keratin and nanoplasty are the ones whose lifestyles include a lot of outdoor time and daily styling fatigue. If you're running the Tan three mornings a week, walking to the Como in summer, riding the bike path from Burnley to the CBD, or working a corporate day in East Melbourne with a gym session after, a smoothing treatment gives you back 30 to 40 minutes a day of styling time. That's the real value.
Inner-east and inner-north clients tend to lean differently. Richmond and Cremorne skew towards nanoplasty for its repair benefits, since so many clients in the tech precinct have foiled blonde that's been worked hard. Fitzroy and Collingwood creatives often lean towards keratin smoothing because they want the frizz control without losing their wave. South Yarra and Prahran clients are more likely to ask for a harder smooth because the Chapel Street aesthetic wants straighter and glossier. Toorak and Hawthorn lean towards nanoplasty because the average client in those suburbs has grey blending or a subtle blonde that they don't want to put through heavy chemistry.
Water hardness in Melbourne inner-east suburbs is low-to-moderate, which actually helps smoothing treatments last. Clients who travel for work to Sydney or Perth often notice their treatment wearing off faster there. If you do travel a lot, a weekly reset with a sulphate-free and sulphate-free shampoo (Kérastase Discipline, Bhave Argan One, or Olaplex No.4 for colour) will protect the treatment longer.
What To Look For When Booking A Smoothing Service
Here's what separates a good smoothing appointment from a bad one.
1. The consultation. Any stylist willing to smooth your hair without first running a hands-on strand test, especially if you've had previous colour, box dye, chemical relaxing, or protein issues, is moving too fast. Ask for a test strand or a sample patch at the nape.
2. Ventilation in the salon. Even with formaldehyde-free treatments, flat-iron vapour is not pleasant to breathe for three hours. A good salon has windows open, ventilation running, or does smoothing in a back room designed for it.
3. The product name. Not the brand positioning, the actual product name. Bhave Keratin Smoothing. Cezanne Classic. Brazilian Blowout Zero. Ask. Write it down. Google the safety data sheet if you want to.
4. Aftercare guidance. Your stylist should give you a 72-hour care sheet, a product recommendation for shampoo and conditioner, and a booking reminder for a bond treatment 4 to 6 weeks in.
5. Price transparency. Smoothing is a long service (2 to 4 hours). A price significantly below market is almost always a red flag, cheaper product, shorter process, less bonding care.
Kohort's smoothing service is Bhave Keratin Smoothing, starting from $250, delivered by Billie who specialises in smoothing work and colour-safe bond-repair services. If your hair has a colour-corrected or fragile-ends history, we often pair the treatment with a K18 Molecular Repair or Olaplex Bonding Treatment first. The goal is a finish that lasts rather than a finish that looks good the day of and crashes out at six weeks.
Frequently Asked Questions
Is keratin smoothing safe during pregnancy?
Traditional formaldehyde-containing formulas are not considered safe during pregnancy. Formaldehyde-free keratin like Bhave may be okay for some, but most GPs and midwives recommend waiting until after birth and after breastfeeding. Always consult your doctor first.
Can I get a keratin treatment and colour on the same day?
Most stylists do the colour first, then wait 1 to 2 weeks before keratin, because the keratin helps lock in colour. Some formulas allow same-day but we always prefer a split appointment for better results.
How soon can I wash my hair after Bhave keratin?
Bhave allows washing 24 hours after the service in most cases, though 48 hours is safer. Don't tie your hair up, use clips, or wear a hat tight to the scalp in those first 24 to 48 hours. The treatment is still settling.
Does nanoplasty straighten curly hair?
No. Nanoplasty is designed to reduce frizz and strengthen the fibre without changing your curl pattern. If you want to straighten curly hair, a keratin smoothing or a Brazilian blowout is the correct choice. For most curl types, we would talk you out of straightening chemically and towards a different approach.
Can smoothing treatments damage bleached hair?
If applied incorrectly, yes. Bleached hair is already compromised, and stacking a keratin or Brazilian on top of that without a bond-repair pre-treatment can tip fragile hair over the edge. A nanoplasty is usually a safer first smoothing treatment for heavily lightened hair.
Will a keratin treatment make my hair fall out?
No. A keratin treatment coats the hair strand, not the scalp. What people sometimes mistake for "fall out" is usually hair that was already on its way out being unclumped by the flat-ironing process. If you're losing visible volume post-keratin, that's a sign the treatment weight is flattening already-fine hair, not that it's causing hair loss.
How often can I get a smoothing treatment?
Most clients rebook at the 3 to 5 month mark. Doing it more frequently than every 10 to 12 weeks is generally unnecessary and starts to build up product. We space out smoothing on fragile hair to every 5 to 6 months.
What's the difference between hair botox and nanoplasty?
"Hair botox" and "nanoplasty" are often used interchangeably. Both are amino-acid-and-botanical based, both reconstruct the fibre rather than straightening it, and both carry less chemical risk than a classic keratin. There are small brand-to-brand differences but the category is the same.
Can I swim in the ocean or chlorine pool after a keratin treatment?
Avoid salt water and chlorine for at least 2 weeks post-treatment, ideally 4. Chlorine strips the keratin bonds quickly. If you swim regularly, wear a cap and rinse hair with fresh water before and after swimming.
Why do some keratin treatments only last 8 weeks?
A short-lived keratin usually means either an inferior formula, rushed application time, not enough flat-iron passes to seal properly, or incorrect aftercare (sulphate shampoos, frequent chlorine, high heat tools). A well-applied professional keratin on properly cared-for hair should last 3 to 5 months minimum.
Can men get keratin treatments?
Yes, all the time. Shorter hair means shorter application, usually 60 to 90 minutes instead of 2 to 4 hours. Men with thick, wavy, or frizzy hair often see the biggest improvement because the ratio of treatment-to-length is high.
Which Treatment Should You Actually Book
If you're still wavering after all of that, the rough rule is:
- Book keratin smoothing (Bhave) if your hair is wavy to loose-curly, frizzy in Melbourne summer, and you want to keep your movement while cutting daily styling time.
- Book nanoplasty if your hair is fine, fragile, coloured, or already been through a correction, and you want frizz control without straightening or weight.
- Reconsider a Brazilian blowout unless you specifically want a hard straight finish and you've verified the formula is formaldehyde-free.
Kohort's smoothing services are run by Billie, who's done hundreds of treatments on everything from fine colour-corrected blondes to coarse resistant waves. Book a free 15-minute consultation if you're not sure which direction to go. We also offer K18 Molecular Repair, Olaplex Bonding Treatment and the Kohort Scalp Ritual as add-ons when a smoothing treatment is part of a bigger hair-health reset.
Explore our keratin smoothing service page for pricing and aftercare, or contact us to book a consultation. The goal is a finish that still looks great when you walk back in three months later, not one that looks great only on the day.
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