Why You Should Never Straighten or Curl Wet Hair



I’ve been straightening and curling my hair wet/damp for years, despite all the popcorn-sounding fizzes and crackles – but some science I’ve recently read have made me do a complete 180. It turns out wet and dry hair respond to extreme heat very differently – and wet hair cops it far worse, and not just because it’s more fragile.

First, a little refresher on hair anatomy. Hair has three main parts:

  • the medulla – boring central core, actually non-existent in light and fine hair
  • the cortex – middle layer, responsible for colour, texture and most of the strength of hair
  • the cuticle – protective outermost layer, made of overlapping cells like roof shingles or fish scales, shiny


The cuticle lays flat, but water can get in between the gaps. When you wet healthy hair, it can actually absorb up to 30% of its own weight in water into the inner spongy cortex (more if it’s damaged hair).

An average hair straightener heats up to 185-230 °C. Curling irons are a little cooler, at 95-200 °C. They’re both well above the normal boiling point of water, which is 100 °C. (Temperatures in Fahrenheit are straighteners 365-446 °F, curlers 203-392 °F and boiling water 212 °F, for any readers from non-metric countries like the US, Liberia or Myanmar.)

C’mon USA, switch already. I believe in you.

What happens when the wet inside of hair gets heated well beyond its boiling point? Well, it’s not too dissimilar to popping corn…


When water turns from liquid to gas it expands. When it’s heated strongly it expands rapidly. Since it’s confined in the cortex by the cuticle, it has to bust out. That’s right – the water explosively evaporates, shattering whatever’s in its path, which happens to be… your hair.

From Gamez-Garcia, J Cosmet Sci 2001, 62, 109-120

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The Science of How Fake Tan Works


These days we’re all aware that suntans give you both cancer and wrinkles, so fake tan is the colour du jour. This miracle-in-a-can stains the skin brown through an interesting chemical reaction. The outer layer of your skin, made up of dead skin cells, is permanently coloured. The tan wears away as the skin cells come off. Here’s how it works, and whether it’s safe!

The Chemistry of Fake Tan

Fake tan products you find in stores contain 2-5% dihydroxyacetone, which looks like this:


It starts off colourless, but it reacts with amino acids (particularly arginine, lysine and histidine) in the skin to form a variety of brown compounds called melanoidins.


It’s actually the same chemical reaction as the one responsible for making food like bread and meat turn brown and delicious when cooked. It’s called the Maillard reaction. For the really intense chem nerds, it proceeds like this with DHA (I got a bit lazy, sorry for the shortcuts):


This forms covalent bonds, which means the skin is permanently stained – water, soap and moisturiser won’t wash it off. The skin starts devloping the tanned colour after 2-3 hours, and the reaction continues for the next 1-3 days. The reaction occurs best at moderately low acidic pHs (3-6), so fake tans tend to come in this skin-friendly range. The extent of the reaction is also influenced by the amount of water around.

Application and Aftercare

DHA only penetrates the very top layer of skin (the stratum corneum), which you may know is dead skin cells. This is why fake tans can’t last longer than about a week – that’s about how long it takes for the stained skin to wear off (that’s why if you look up fake tans that claim to last longer than a week or two, you’ll find tons of grumpy reviews – the skin sheds at a similar rate no matter what product you use!).

This explains all the advice given for making your tan look good and wear off evenly:

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Fact-check: What’s to blame for the Mentality Nail Polish problems?


Update (2018-12-05): Since Danny of Mentality Nail Polish has generously sent me a cease and desist for defamation as seen in the comments section, I’d like to interrupt your regularly scheduled programming to clarify (even though I think it’s pretty damn clear already) that the causes of the issues are science-based opinion and speculation. 

Welcome to every nail polish lover’s nightmare – nail disease. Wearers of Mentality Nail Polish have been waking up to this horror: mentality-nail-detachment-dmm-nails

mentality-nail-detachment-dmm-nails Thanks to @dmm_nails for letting me use images of her poor nails!

The technical term for this is onycholysis – when your nail detaches from the underlying nail bed. It’s painful, it’s inconvenient, it’s ugly, and you have to wait til it grows out to recover (if it ever does). There are lots of write-ups on the multitude of legal and ethical fuck-ups that Mentality Nail Polish have made in handling this issue, so I’m not going to rehash that in this post (you can read all about it at The Mercurial Magpie and Ashley Is Polish Addicted, amongst others). Like many others, I’ve been racking my brains wondering what exactly went wrong.

Of course, we won’t know for sure until someone gets analysis results back from a lab. Mentality “almost have enough funds” for an analysis now (although they’ve reportedly known about this problem since September last year, and a GCMS can ordered for under $100 and they haven’t even done that, so I’m guessing we’ll hear the results in 2020 or after an injunction?). But since they’re going full Laganja on this one, I’m not holding my breath.


In the meantime, here’s my analysis of all the speculations that have been flying around. Keep in mind that these are just speculative hypotheses and my opinions on them only – they’ll change as we get more complete information (which is pretty tricky, as Mentality have been deleting their posts, and I’m having trouble finding some of their past statements… I’m sure a lot of links I currently have here will die!). As I’ve read more, I’ve changed my mind about 7 times about what I think the most likely cause is. I’ll be updating the possible explanations as they develop.

What we know

  • Indie makers typically buy a pre-made base from a larger manufacturer, then add tints and glitters. This is what Mentality have supposedly been doing.
  • From Mentality’s Facebook page:
    • Mentality were using Tevco and Fiabila base (3/4 free), but sometime late last year/early this year they switched to a base from Arminex (5 free – parent company of Nubar). They’ve since switched back. They do not make nail polish base themselves… “yet”.
    • The problematic polishes aren’t isolated to the neons, although the neons were very popular and consumed whole barrels of the base, so they’re the most commonly reported.
    • Mentality degassed all the bases to “remove air bubbles and found that Arminex base is very foamy, compared to the other manufacturers whose polish base does not foam upon degassing.”
    • Not everyone who wore them were affected (around 40 people have reported reactions to Mentality so far). The earliest case was @spilledmilknails, a Mentality swatcher, in September 2014.
  • From people who own the affected polishes:
    • The polishes with the different base smell very “chemical” “like melted plastic”, and the smell seems to have gotten worse over time.
    • Some people were reporting stinging, itching and redness upon application.
    • People who experienced nail detachment generally wore them for longer periods, while swatchers who removed them immediately were generally affected less. There are exceptions though – apparently someone swatched them for 4 hours and ended up with nail damage a few days later.

Faulty Arminex Base Theories

This is the angle that Mentality have been pushing, which makes sense because it means less liability for them and hence their best chance of getting out of this without being buried in a steaming turdpile of legal troubles.

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Fact-check: How does IBX Nail Strengthening Treatment Work?


If you’re in the nail world, you’d have heard of IBX, the nail strengthening treatment that’s been saving nails everywhere. How does it work, you ask? Here’s the science!


What is IBX?

IBX is a nail strengthening treatment described as “a penetrative, curable monomer system”, developed by Famous Name, a company headed by the ex-CEO of CND and his wife. It consists of two bottles of liquid containing monomers, small molecules that can join together, as well as a photoinitiator which starts their joining when the right type of light is used. First, IBX Repair is applied to the visibly damaged parts of the nail and cured, then regular IBX is applied to the nail and cured. The results look pretty amazing:


As well as healing splits and peels, it also fills in grooves and adds a protective layer to your natural nail so it can grow out further without breaking, and shields it from further abuse, like gel polish removal. Pretty awesome, right? Turns out that the way it works is pretty nifty too! (I’m not getting paid to write this by the way – just sayin’.)

How does IBX work?

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Fact-check: Does Tea Tree Oil Work?



Tea tree oil is probably something you’ve seen at the beauty counter dozens of times, in skincare creams and ointments. But what is it used for?

What’s tea tree oil?

Tea tree oil comes from the leaves of the Melaleuca alternifolia shrub (common name tea tree, surprise surprise!). This tree is native to Eastern Australia. The oil is colourless to light yellow, and smells strongly pine-like. If eaten, it’s poisonous to both humans and animals.

In skincare, tea tree oil is useful because it’s antibacterial – pimples contain the bacteria Propionibacterium acnes (commonly abbreviated as P. acnes), and killing these reduce acne (many other acne treatments, like benzoyl peroxide and the antibiotics clindamycin and erythromycin, also directly kill acne bacteria). It also kills fungi, which means it’s handy for nail and foot infections too.

How do I use it?

If undiluted, tea tree oil can be irritating, so diluting it in another oil like mineral oil or sunflower oil is the best way to use it. A study found that 5% tea tree oil works as well as 5% benzoyl peroxide – it acts more slowly, but it’s less irritating, so 5% is a good starting point if you’re not sure.

5% tea tree oil means if you want a total of X mL tea tree oil mixture, to get the mL of:

Tea tree oil: multiply the total X by 0.05
Diluting oil: multiply the total X by 0.95

Then mix the two together in a clean bottle to get your mixture!

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Fact-check: The Lead in Lipstick is Safe



This “lead in lipstick” hoax has been going around Facebook again – it’s actually pretty ancient (goes back to the early 2000s) and refuses to die. Here’s one version:


All the versions of this chain email are slightly different but all have the same themes… and all are BS. There’s a whole bunch of wrong in this scary-sounding PSA.


Recently a brand called “Red Earth” decreased their prices from $67 to $9.90.

This bloody factoid changes currencies all the damn time – let’s pretend it’s in Australian dollars, cos it’s probably the way it’ll make most sense. Red Earth was never $67, and it sure as hell isn’t $9.90 now. Even if you don’t know science, you should know that Red Earth is a comfortable $24.

Why? Because it contained lead.

This is true. BECAUSE EVERYTHING CONTAINS LEAD. The thing is, atoms and molecules are really really really really really really ridiculously tiny. According to some maths, each of us contains about 200 billion of Shakespeare’s atoms (and 200 billion atoms from anyone else who’s ever lived and been dead for a while), so it’s not surprising that in your lipstick, there’s at least one atom of an element that was spewing into the atmosphere for 80 years thanks to leaded petrol. So a “trace amount of lead” is unavoidable in everything outside of the most high tech, fanciest lab.

So the real question is, how much lead is there? They’ve got one thing right:

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Do oils make your skin less oily? The myth of rebound oil

You’ve probably seen the concept of rebound oil production, or reactive seborrhea: “shampoos… strip the scalp of its natural oils and cause the scalp to overproduce oil to compensate” “our skin naturally regulates perfect oil production” “your skin will have to adjust to producing less oil” “the oil tells the skin it’s no longer drying out, which helps to control …

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Fact-check: “Solvent-Free” Nail Polish Removers

For years, we’ve been using just 2 solvents, ethyl acetate and acetone, to remove nail polish. But recently a whole host of new removers containing neither of those have made their way onto the market – what are they, and are they worth a shot? Are they really solvent-free? No. Anything that dissolves something else up is a solvent – …

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