Do peeling gels really peel off my skin? (with video)

“Is all the stuff that rolls off with a peeling gel really my skin?“ This is a question I come across a lot! In case you’ve forgotten, a peeling gel is a popular type of cleanser in Asia. You start off with a watery gel like this, which you spread over your face (the one picture here is Laneige Strawberry …

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How Does the Clarisonic Cleansing Brush (Theoretically) Work?

How Does the Clarisonic Brush (Theoretically) Work?

How Does the Clarisonic Brush (Theoretically) Work?

I always assumed that the Clarisonic cleansing brush was an attempt to clean the skin via sonic cavitation, which is when sound waves cause tiny jets of water to smash into a surface to clean it, like a thousand tiny power hoses (that’s how sonic jewellery/glasses cleaners work). But for sonic cleaning via cavitation to work, you need a hard surface, which glasses and jewellery are, but skin is not, so I was pretty confused.

I recently stumbled upon a paper from 2006 in the Journal of Cosmetic Dermatology, where the inventors of the Clarisonic discuss how it’s designed to work. (Important note: the paper doesn’t present any data of the Clarisonic in action to show that that’s how it actually works, but it’s interesting to see the theoretical background anyway!)

The Clarisonic Brush Head

The Clarisonic brush head has two parts: an outer ring that’s fixed and doesn’t move, and an inner section that’s attached to a motor inside the handle.

From the Clarisonic patents, the inner section rotates back and forth between 8 and 26°, at a frequency of 176 Hz (i.e. it makes 176 cycles from the left to the right and back again in a second; you can also think of it as 352 “sweeps”).

How Does the Clarisonic Brush (Theoretically) Work?

How the Clarisonic Brush Head Works

Here’s the question: if you put the brush against your skin, which part of your skin gets cleaned the most? If you’re a normal sensible person who hasn’t looked at the Clarisonic website in much detail, you’d say, “the part of your skin that’s sitting under the moving inner portion.”

This is where it gets really interesting – the part of the skin that the brush is designed to deeply clean is actually the part with no bristles on it! It’s the skinny ring in between the outer and inner portions (0.05-0.125 inches, or 1.3-3.2 mm according to the patents).

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Make Your Own Soap! Part 2: Let’s Make Some Soap!

It’s the second part of my soap making post! Last time we looked at the chemistry behind soap making (also called saponification) – today we’re looking at how to actually make a bar of soap, using ingredients from the supermarket. From the previous chemistry post, we know that we’ll be mixing some oils with sodium hydroxide to form glycerin and …

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Make Your Own Soap! Part 1: The Chemistry Behind Soap Making

In the middle of teaching some high school students about the chemistry of soap-making, I realised that I really, really wanted to try making some soap myself and write about it here. My write-up ended up being really long, so I’ve made it a two-parter – Installment 1 is all about the chemistry, and Installment 2 is about the actual …

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A Month Without Facewash

I’ve had a sneaking suspicion that you could oil cleanse without using a regular cleanser afterwards, if you repeatedly wiped off the old oil and added more oil to dilute the dirt (not quite what I said in this early post – but that was assuming that you only wipe oil on your face once). So naturally I had to …

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Do pores really open? And all about thermal cleansers

I’ve recently started trying out thermal cleansers. These are special cleansers that heat up when you rub them on your skin and add water. What’s the point of them and how do they work? I’m glad you asked, hypothetical reader! Do pores open with heat? Heat makes muscles relax, while cold makes muscles contract (you may know this from treating …

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Fact-check Friday: Do Stridex products have the right pH to work?

Note: This information is not quite correct. There’s some evidence to show that the pH of salicylic acid products isn’t that important to how well they work – for a longer explanation check out this post on pH and AHAs and BHAs. ——————————- Stridex “in the red box”, manufactured by Blistex, is a cult product that’s worthy of the hype …

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Concealer creasing comparison 2.0 – Collection 2000 vs MAC

After my original concealer creasing comparison here, I did some digging around to see if there were other concealers that could compare to MAC Pro Longwear. I’ve had a terrible run with MAC breaking me out (and my skin is pretty hardy), so I wanted to try my luck with other brands. I also disliked the packaging of MAC Pro …

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