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

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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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Why You Shouldn’t Use Lemon Juice on Your Skin

There are more DIY skincare recipes on the internet than you can shake a stick at, and most of them really, really like lemon juice. According to these DIY tips you should be slathering it all over your face and hair. Lemon juice smells nice, and it’s pretty cheap. But is it effective? And is it safe? Let’s talk about …

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DIY Mattifying Face Powder: Just a bag of corn starch

DIY Mattifying Face Powder: Just a bag of corn starch

The latest high-impact addition to my make-up stash has been a $2 sack of corn starch. No, I haven’t turned into a “if you can’t eat it, don’t put it on your face” woo-meister… here’s the lowdown.

DIY Mattifying Face Powder: Just a bag of corn starch

Why Am I Putting Corn Starch on My Face?

I am an oily beast. My skin is generally hydrated and non-irritated, so it’s not my skin overproducing oil – it’s just naturally oily.

This means I tend not to wear moisturiser during the day, and even them my make-up will generally slide around and bunch up during the day. There are a few things I’ve found really handy for dealing with it, and one of the most effective things has been using a starch-based face powder.

DIY Mattifying Face Powder: Just a bag of corn starch

I’ve tried a lot of different translucent powders to try to soak up oil, but the one that have worked best for me so far have been Williamspro Zero Powder, Jurlique Rose Silk Finishing Powder and Innisfree No Sebum Mineral Powder. Their top 3 ingredients:

  • Williamspro Zero Powder: Certified Organic Arrowroot Powder, Australian Green Clay, Australian White Clay
  • Jurlique Rose Silk Finishing Powder: Zea mays (Corn) Starch, Oryza sativa (Rice) Starch, Silica
  • Innisfree No Sebum Mineral Powder (now slightly reformulated and called Matte Mineral Setting Powder): Silica, Corn Starch Modified, Dimethicone/Vinyl Dimethicone Crosspolymer

So you can see – the top ingredients all include some form of starch.

There’s also been a trend of people using talcum powder on their face, so I unearthed this from Amazon:

Johnson’s Pure Cornstarch Baby Powder With Aloe Vera & Vitamin E

Ingredients: Zea Mays (Corn) Starch, Tricalcium Phosphate, Aloe Barbadensis, Tocopheryl Acetate (Vitamin E), Fragrance

Note: no preservative. So why not try corn starch from the grocery aisle?

Issues with Corn Starch as Face Powder and Solutions

These are the most common objections to using food-grade corn starch as face powder that I’ve come across:

Corn starch can grow bacteria/fungus while in the container

This is probably the most common one: corn starch is food, and can breed fungus and bacteria while in the container. If you put that on your face, it can give you breakouts.

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Video: Are Natural Beauty Products Better?

Video: Are Natural Beauty Products Better?

I’ve uploaded a new video on whether natural beauty products are better or safer. This is a topic that’s close to my heart, as it was the reason I started my blog all the way back in 2011 and it was my first science post! So I donned my best natural-themed jacket and recorded this. Check out the video here. …

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What’s the deal with fermented skincare?

What's the deal with fermented skincare?

There’s a lot of buzz about fermented ingredients in skincare. It’s been a big hit in Korea, with entire product lines revolving around the idea of letting ingredients marinate for a bit longer. Here’s the science behind fermentation.

What is fermentation?

Fermentation refers to chemical reactions performed using microorganisms. More specifically, it usually means reactions that convert sugars to other substances. Fermentation’s been known for thousands of years – for example, yeast is used to ferment sugar in grapes to make wine, and bacteria are used to produce vinegar. A lot of fermented foods like kombucha, kimchi and kefir are trending thanks to increased awareness of the importance of gut flora (and for some weird reason, they tend to start with the letter K…).

What's the deal with fermented skincare?

Since it’s such a broad category of reaction, it’s hard to make broad generalisations about fermented products. In the realm of food, adding fermented products to your diet can improve gut health, increase nutrient availability and reduce the risk of some cancers… or it can double your risk of oesophageal cancer, or suck $100 billion from the US government each year.

Fermented skincare

Just like with food, it’s impossible to make sweeping statments about fermented ingredients in skincare.

Brands that emphasise the benefits of ferments in skincare usually claim that fermentation breaks ingredients down into smaller fragments so they’re easier to absorb. While it’s true that skin absorbs smaller ingredients more easily, that’s only useful if they haven’t been broken down to the point where they’re no longer active.

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Skincare Products I Hate and Do Not Recommend

Skincare Products I Hate and Do Not Recommend

I’ve done a lot of posts on skincare products I love… now, for something a bit different, here are some that I really hate and would only recommend to people I don’t like. So if I ever recommend these to you… it’s not me, it’s you. I just don’t see our relationship working out.

Skincare Products I Hate and Do Not Recommend

Coffee Scrubs

Coffee scrubs are made from coffee grounds, which is literally the stuff you chuck into the bin after making coffee. Now I’m sure there’s a little bit of work involved in making sure it doesn’t mould away in the packet, but essentially you’re buying rubbish at $30 for a small bag.

How can they charge this much, you ask? Well, it’s because they usually claim to get rid of cellulite. This is a bald-faced lie, because apart from the fact that you can’t actually get rid of cellulite, one application of the amount of caffeine required to make cellulite look a little better equates to 2.1 kg of coffee grounds, left on your skin for hours. Any improvement you get is probably mostly a combination of massage, exfoliation and placebo, which really shouldn’t cost that much.

Coffee scrubs are also messy as hell – unlike sugar and salt scrubs, they don’t dissolve in water so gritty black specks will lurk in unexpected places forever. I’m still finding bits of coffee grounds under my soap despite rinsing my entire shower down with vinegar the one time I tried one.

I suppose there’s nothing really harmful about coffee scrubs, really. What pisses me off is mostly just the SHEER AUDACITY of charging so much for a product that’s worse than salt mixed with a bit of oil (about $1.10 a kg, if you shell out for the nice oil). It’s more expensive than a whole bunch of other great exfoliants, and it’s basically bagged up garbage. I wish I’d thought of it.

What you should use instead: Salt + oil, or a leave-on anti-cellulite caffeine cream.

Apricot Scrubs with Shell Bits

First off, physical exfoliation is not the devil. It’s a great thing to use in conjunction with chemical exfoliants. But apricot scrubs containing ground walnut shell… that’s a different matter entirely.

As far as I can tell with my trusty literature review tools, there isn’t any evidence that they cause microtears which harbour bacteria (and I have no idea how that rumour started, but if you know anything about it I’d love to hear from you!), and there are many beneficial products and procedures with harder particles (hello microdermabrasion). But maybe half of the “skincare-naive” people who ask me about their skin problems have this on their bathroom shelf, and they use way too much pressure when scrubbing, and do it way too often (for some reason people feel the need to use it once a day). This sort of treatment usually starts by giving you a nice glow, but it’s unsustainable and quickly leads to sensitive, dehydrated, compromised skin that feels rough and is prone to breakouts. Of course, the obvious thing to do is to use more of the product to get that nice glow back, but it’s a downward spiral from there.

I don’t think St Ives deserves to be sued, but I also wouldn’t lose any sleep if apricot scrubs disappeared. (Also, why are they all called apricot scrubs instead of walnut scrubs?)

Skincare Products I Hate and Do Not Recommend

What to use instead: Any gentler physical exfoliant: konjac sponges, sugar scrubs, cleansing brushes. If you don’t already have an exfoliation routine in place, I’d recommend setting one up.

Soaps for the Face

True or “natural” soaps that is, made from lye or caustic potash and fats or oils. This includes products like African black soap and Castille soap. Soap is bad news for your face for a couple of reasons:

  • It’s impossible for soap to work at a pH lower than around 9.5, which is unfortunate because your face has a pH of 4-6, and high pH will disrupt your skin’s ability to stay intact
  • Soap’s structure (straight tail, small head group) makes it awesome at messing up the proteins in your skin

Some people with tolerant skin will be able to handle soap on their face, and most people can use it on tougher body skin with no big dramas, but a lot of companies that sell soap as facewash go for the “gentle, great for sensitive skin, BECAUSE IT’S NATURAL” angle.


If your skin is sensitive, soap is not great for it (dehydration, breakouts and roughness galore), and soap isn’t much more natural than gentler cleansing ingredients anyway. Soap is fats and oils which have been reacted to turn it into something else entirely, much like how plastic is made by reacting dead dinosaurs.

What you should use instead: A gentle face cleanser that’s formulated with surfactants made for mildness. Check out this gentle cleansing guide for tips on how to pick a good product and some suggestions.

Hypoallergenic Natural Products Loaded with Essential Oils

On a similar note, the “gentle, great for sensitive skin, BECAUSE IT’S NATURAL” brigade are also really fond of jamming essential oils into products to somehow make them less reactive. Which is entirely the wrong direction to go, because fragrance is one of the things that people with sensitive skin are frequently sensitive to, and guess what – essential oils are fragrant (and plant extracts usually are too). In fact, many synthetic fragrances are just essential oils with some chemicals taken out. That’s why a whole bunch of “natural” skincare products have a list of chemicals at the end of their ingredients, like linalool, benzyl alcohol, geraniol and coumarin – these ingredients known to cause allergies in susceptible people are usually hidden in essential oils and plant extracts, but EU regulations require that they be listed.

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All About Bee Venom and Honey in Skincare

All About Bee Venom and Honey in Skincare

Honey and bee venom have been used in folk medicine for thousands of years, but they’ve made a recent resurgence in skincare. Here’s the science behind these ingredients. Honey in Skincare Honey is formed from nectar and pollen by bees through a process of partial digestion (don’t think too hard about it if you want to enjoy honey ever again). …

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Vitamin C Serum Reviews: Indeed Labs and Ole Henriksen

Vitamin C Serum Reviews: Indeed Labs and Ole Henriksen

I’ve recently tried two vitamin C products: Indeed Laboratories Vitamin C24 and Ole Henriksen Truth Serum Vitamin C Collagen Booster. I got into vitamin C products a while back through the Obagi serum as a way to fade sun freckles on my hyperpigmentation-prone skin (Fitzpatrick type III, which in my opinion is one of the worst types if you’re prone to hyperpigmentation, because not only do you get pigmentation easily, but it also contrasts more with the rest of your skin). Vitamin C has other benefits too, such as promoting collagen synthesis (plumps up skin and reduces wrinkle depth), soaking up sun damage as an antioxidant, and fading acne scars (post-inflammatory hyperpigmentation or PIH).

The annoying thing about vitamin C in skincare is that it tends to be very unstable, breaking down rapidly to dehydroascorbic acid in the presence of light, water and oxygen, and doesn’t penetrate the skin easily (it generally needs to be at pH < 3.5 for it to be unionised and hence penetrate skin better). Both these products manage to get around these issues.

Vitamin C Serum Reviews: Indeed Labs and Ole Henriksen

Indeed Labs Vitamin C24

Indeed Labs Vitamin C24 ($36.99 for 30 mL) is a white cream-like product that comes in a squeezy tube. It gets its name from the 22% L-ascorbic acid and 2% hyaluronic microspheres that it contains. Here’s the ingredients list:

Dimethicone, Ascorbic Acid, Polysilicone-11, Ethylhexyl Palmitate, PEG-10 Dimethicone, Silica Silylate, Silica Dimethyl Silylate, Butylene Glycol, Sodium Hyaluronate

The first thing you’ll notice is that this product doesn’t contain water. This is significant for two reasons:

  1. Water speeds up the decomposition of L-ascorbic acid to inactive dehydroascorbic acid, so using a water-free (anhydrous) formula keeps the vitamin C levels higher for far longer, translating to a more effective product.
  2. Only water-based products have a pH, and since the cream is oil-based, L-ascorbic acid will be unionised and can penetrate the skin quickly, again increasing effectiveness.

22% vitamin C matches the amount used in an in vitro experiment which used anhydrous vitamin C to increase collagen levels, although a small clinical study found that 10% already had good anti-aging effects. I found that it prickled a bit after applying it to my face – probably a result of the vitamin C dissolving in tiny amounts of water on my skin or in the air.

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