Skincare Oils and Free Fatty Acids: The Science (with video)

Video: Skincare Oils and Free Fatty Acids: The Science

If you’re a skincare nerd, you may know that different skincare oils have different fatty acid profiles – that is, they differ in terms of which fatty acids they contain e.g. linoleic, linolenic, oleic and lauric acid. The fatty acids have interesting properties. For example, lauric acid is strongly antibacterial, and works better than benzoyl peroxide against Cutibacterium acnes bacteria. …

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How much UV does a REAL mineral sunscreen absorb and scatter?

sunscreen center mount

Warning: Very nerdy content ahead! If you’ve been following sunscreen discourse (apparently this is a thing now) you’ll know that mineral sunscreens mostly work by absorbing UV and only scattering a small amount, in the region of 4-5% across the range of UV. This was quantified in a pretty commonly cited 2016 paper by Curtis Cole, Thomas Shyr and Hao Ou-Yang, “Metal …

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Clean Beauty Is Wrong and Won’t Give Us Safer Products

Think Dirty App

If you use beauty products, it’s impossible to not have heard of clean beauty. It’s a revolution. You want your products to be clean – you don’t want to use dirty products! You want your products to be good for your health and good for the environment. There are beautiful celebrities telling you about how they detoxed and cleaned out …

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Sunscreens in your blood??! That FDA study

sunscreen-jama-study

You’ve probably seen the recent influx of articles about the new FDA sunscreen study, usually titled something like “sunscreens can make it to your bloodstream!” The study itself is fine and good and necessary as a first step in the FDA’s new zeal for sunscreen regulation. But the more I read the coverage around it, the more annoyed I get, …

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Amodimethicone: The Science of My Favourite Hair Ingredient

Amodimethicone: My New Favourite Hair Ingredient

Since I bleached my hair and dyed it purple (and am now slowly shifting to pink), my hair care needs have changed massively. Typical straight, black East Asian hair naturally has low porosity, with the outside cuticle lying very flat. This means that water and other ingredients don’t go in or out of the hair strand easily, so using the …

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Skincare Chemistry: How to pick out humectants

humectant

I recently posted an excerpt from The Lab Muffin Guide to Basic Skincare on my Instagram and Facebook (which is one of many useful tables in my eBook by the way, and it’s packed full of information on the super important fundamentals of science-based skincare – although I’m obviously biased since I wrote it and put all my best tips …

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Is Sodium Hydroxide Safe in Beauty Products?

Is Sodium Hydroxide Safe in Beauty Products?

Sodium hydroxide is in a ton of beauty products. But as one of my favourite unreliable sources says (the “favourite” is sarcastic by the way, just to clarify): Sodium Hydroxide is, however, a known irritant… The National Institute for Occupation Safety and Health … recommends that consumers prevent skin and eye contact The CDC reports that “Skin contact with sodium …

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Activated Charcoal in Skincare: The Science

activated-charcoal-cleansing-mechanism

Activated charcoal skincare products are pretty cool. They’re black, they’re sciencey-sounding and they’re said to suck dirt out of your pores like a magnet – what’s not to like? The reality is a little more complex than that…

(If you’re after the video version of this post, check it out here! To make sure you don’t miss a video from me when it goes live, click here.)

What is activated charcoal?

Activated_Carbon
Source

Activated charcoal is carbon soot that’s been treated to give it a sponge-like structure, with lots of holes. If you zoom into activated charcoal, it’s very jaggedy, giving it a huge surface area. It’s estimated that 1 gram of activated charcoal has a surface area of 3000 square metres, which is the same as 3 Olympic swimming pools, 7 basketball courts or 230 car parking spaces.

Activated_Charcoal-microscope
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This gigantic surface area is particularly handy for soaking up substances. You can see how effective it can be for purifying water in the picture underneath, where activated charcoal’s grabbed onto all the red dye in the glass on the left (it can also be seen with the orange fizzy drink in the video).

Activated_carbon-red-dye-adsorption

In medicine, activated charcoal is mostly used in poisoning cases, where a large dose is fed to the patient alongside other treatments. A lot of the poison sticks to the charcoal instead of absorbing into the body.

Since it’s a default treatment for soaking up ACTUAL TOXINS in poisoning, lots of people eat/drink activated charcoal for “detox” purposes, which sounds like it could work (although if you read my other blog, you’ll know that detox is a scam). You might be wondering, how does activated charcoal tell the difference between good things and bad things? The answer is… it doesn’t.

How does activated charcoal work?

At a molecular level, things are sticky. It’s why the wax in a candle stays together as one big clump instead of splaying everywhere, and why you have to put in a whole heap of heat to get water molecules to separate and turn into steam. This stickiness is known as intermolecular forces – interactions that stick molecules together. Without them, everything would be a gas.

There are a few types of intermolecular force – the one that activated charcoal uses is called dispersion forces. Absolutely every substance has dispersion forces, whether it’s a vitamin or a poison.

Remember the large surface area that activated charcoal has? This means there’s a lot of space for things to stick to. And since everything can form dispersion forces, activated charcoal actually soaks up all sorts of things, including nutrients like vitamins, meaning you don’t get the full health benefits of your food.

Activated charcoal can stick to medications as well, if they’re still in your digestive system. This means that you might not be getting the right dose.

In a poisoning situation, you’re probably not worried about whether you get enough vitamins, but in everyday life it’s not such a good idea to prevent your body from taking up random nutrients and medications on a regular basis. So don’t make activated charcoal part of your regular diet!

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