Ingredient Watch: Benzoyl Peroxide

Today's Ingredient Watch post is about benzoyl peroxide, an ingredient present in most over the counter anti-acne treatments. It is also used in skincare products, teeth whitening products and hair dyes.

Important Note: Let me just preface this post by saying I am not a dermatologist or medical professional. Within this and all past and future posts discussing beauty product ingredients, my aim is to collate and summarise information and present it in a way that is accessible and informative. I will always use the most reliable sources of information available to me, and attempt to present it in an honest and unbiased way. If you feel that any of my posts have incorrect information, or you believe there is something important to add, please don’t hesitate to let me know by leaving a comment or emailing me at theglowdown@gmail.com. It is important to me that I get it right.

What does it do: Benzoyl peroxide does a number of things, including:

·        Acting as a peeling agent or chemical exfoliant, it helps to lift the upper skin layers and increase the rate of skin turn over

·        Clearing pores of dead skin cells, preventing blemishes caused by blockages

·        Creating an oxygen rich environment within the pore, killing the bacteria that commonly causes acne

·        Lightening and whitening teeth and hair

The Good: Benzoyl peroxide is very effective in preventing and reducing breakouts. By helping to remove the top layers of dead skin, it also helps to make the skin look more radiant and even.

The Bad: Most users experience dryness and mild irritation initially, which usually subsides in a week or two, while the skin acclimates. Other, more serious, but less common side-effects include burning, itching, swelling and peeling.

The Ugly: In the 1990’s benzoyl peroxide was thought to be a carcinogen, or cancer causing chemical. More recent studies have been unable to find evidence of this. The FDA in the US classifies it as a chemical safe and effective for over the counter topical treatments.

Some Considerations When Using: Benzoyl peroxide does irritate the skin. If you are new to using products containing the chemical, using lower doses (2.5% or less) to start with is advisable. If you experience mild skin irritation and dryness for more than two weeks, or moderate to severe irritation, cease using products containing the chemical.

How To Find It On The Label: As far as I can tell, it is simply labelled as benzoyl peroxide. If anyone knows of any other names or codes it is labelled as, comment below and let me know.

Ingredient Watch: Glycerin

Today’s ingredient watch is all about glycerin (aka glycerine or glycerol). Glycerin is a colourless, odourless thick liquid used in a whole host of beauty and medical products.

Important Note: Let me just preface this post by saying I am not a dermatologist or medical professional. Within this and all past and future posts discussing beauty product ingredients, my aim is to collate and summarise information and present it in a way that is accessible and informative. I will always use the most reliable sources of information available to me, and attempt to present it in an honest and unbiased way. If you feel that any of my posts have incorrect information, or you believe there is something important to add, please don’t hesitate to let me know by leaving a comment or emailing me at theglowdown@gmail.com. It is important to me that I get it right.

What does it do: Glycerin is included in beauty products for a whole host of reasons. It is a very good solvent, it can improve the texture and smoothness of formulations, it can lubricate formulations, making them more slick and also acts as an antibacterial. But, one of its big uses in beauty is its ability to soften the skin. It’s softening abilities are so significant, it is very commonly used for conditions like psoriasis, and is recommended (even in pure concentrations) for people with sensitive skin.

There appears to be some debate as to how glycerin acts to moisturise and soften the skin. One theory is that it does so by drawing moisture from the air to deposit into the skin, another is that it draws moisture up from deeper tissue and yet another is that there is some unknown property that makes glycerin inherently moisturising.

The Good: Glycerin is a relatively gentle chemical, and can even be applied to the skin in pure concentrations. Glycerin’s moisturising abilities and gentleness make it perfect for sensitive skin and dry skin conditions.

The Bad: Glycerin use doesn’t seem to have many side effects. From pretty much all the information I found, it appears to be a fairly safe chemical for most adults.  It has a very low toxicity and can even be ingested.

Like with any chemical, there is always a risk of allergic reaction.

Some Considerations When Using: Not a lot is known about the safety of glycerin use for pregnant or breast-feeding women.

How To Find It On The Label: It will usually be listed as glycerin, glycerine or glycerol on beauty products. In food products it is labelled as E422

If you haven't already, check out my previous Ingredient Watch posts on propylene glycol and salicylic acid.

Ingredient Watch: Propylene Glycol

Today’s focus ingredient is Propylene Glycol (PG), a chemical found in a whole range of beauty products, including hair care, soaps, moisturisers, lipstick, anti-acne products, mascara, toothpaste, deodorant, perfume, mascara, as well as some foods.

Important Note: Let me just preface this post by saying I am not a dermatologist or medical professional. Within this and all past and future posts discussing beauty product ingredients, my aim is to collate and summarise information and present it in a way that is accessible and informative. I will always use the most reliable sources of information available to me, and attempt to present it in an honest and unbiased way. If you feel that any of my posts have incorrect information, or you believe there is something important to add, please don’t hesitate to let me know by leaving a comment or emailing me at theglowdown@gmail.com. It is important to me that I get it right.

What does it do: PG does a range of things. One of its main uses in beauty products is to help formulations maintain their consistency and stop them from separating.  Another is to chemically alter the structure of the skin, allowing other chemicals to penetrate deeper.

In food, it is most commonly used as an anti-freeze.

The Good: It maintains an even spread of ingredients and prevents insoluble ingredients, like oils, from separating. It can also improve the effectiveness of ingredients that need to be deeper into the skin.

The Bad: PG has been known to cause allergic reactions in some users, and exasperate conditions like eczema and other skin allergies.

Dangers: The dangers associated with PG are very controversial. There does not appear to be much agreement between professionals or the research as to how dangerous or toxic the chemical is. Once of the big concerns is that PG could be a cancer causing carcinogen. Studies conducted on animals using low doses of PG found no increase in the likelihood of cancer. I could not find any studies on the carcinogenic effects of PG in cosmetic products on humans.

Another concern is that PG can lead to organ damage. It has been linked with skin, liver and kidney damage, however, this has only been proven to be an issue with inhaled, injected or ingested doses of PG. A couple of studies identified a small toxic effect following regular topical applications of products with PG in them, and others found no such effects.

Some Considerations When Using: The use of PG is monitored and limited in most countries. Because of how unknown the toxicity of PG when used in beauty products is, I would definitely say any product containing it is one that you should always follow the directions for use for. It is also probably advisable to limit the number of products you use that include PG, and try to avoid products containing it that you are likely to use every day.

How To Find It On The Label: How PG is labelled will depend on your country and the manufacturer. Some common ways it is labelled are as Propylene Glycol; Methylethy Glycol; 1,2-Dihydroxypropane; 2-Hydroxypropanol; 1,2-Propanediol and Propane-1,2-Diol. In foods, it is commonly labelled as E1520 or E490. You can find a fairly comprehensive list of beauty products containing PG here.


If you haven't already, please check out my post on Salicylic Acid.

First Ever Ingredient Watch: Salicylic Acid

Welcome to first ever instalment of Ingredient Watch. In today’s society we are becoming ever more aware of the ingredients we use in our beauty products. In these posts, I aim to bring my readers information about some of the common ingredients in the products we use, including their positive and negative effects. 

Important Note: Let me just preface this post by saying I am not a dermatologist or medical professional. Within this and all future posts discussing beauty product ingredients, my aim is to collate and summarise information and present it to my readers in a way that is accessible and informative. I will always use the most reliable sources of information available to me, and attempt to present it in an honest and unbiased way. If you feel that any of my posts have incorrect information, or you believe there is something important to add, please don’t hesitate to let me know by leaving a comment or emailing me at theglowdown@gmail.com. It is important to me that I get it right.

Today’s focus ingredient is Salicylic acid, a chemical commonly found in anti-acne products.

What does it do: Salicylic acid acts as a chemical exfoliant, removing dead skin cells and unclogging pores and blackheads, as well as an anti-inflammatory, reducing the swelling and redness associated with acne. 

It is also used in combination with other ingredients to soften or loosen the upper layer of the skin to improve the ability of additional ingredients to be absorbed.

The Good: It really does do what it claims to when it comes to exfoliating and reducing swelling.

The Bad: Use of products involving Salicylic acid may lead to dryness  (especially for those with already dry skin) and hair weakness, potentially resulting in temporary thinning or loss of hair over time.

Dangers: If used in high concentrations, Salicylic acid is capable of causing chemical burns. It has also been linked to tinnitus (ringing of the ears) and reversible hearing loss when ingested.

Although rare, allergic reactions are also possible.

Some Considerations When Using: In most countries, the concentration of Salicylic acid in over the counter products is regulated. Usually this is around 2% for products that are likely to stay on the skin for a period of time and 3% for those that will be immediately washed off.  Because of this difference in concentration, it is always advisable to follow the manufacturers’ instructions during use. If you experience any dryness, hair weakness or other mild reactions, reduce the frequency with which you are using the product. If you experience a stronger reaction, stop using the product and/or consult a dermatologist.

When Not to Use: Use during pregnancy is not advised, as the effect of topical Salicycilic acid products on pregnancy is unknown.

So, there you have it. Please let me know if you have any thoughts on Salicylic acid, and whether you found this post useful or informative.