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Are bar cleansers bad for skin? Episode 69

Do bar cleansers really clog your pores? Tune in to this week’s show to learn the truth about soaps and other bar cleansers. 

Valentines day and beauty science

It turns out that for every major Valentine’s Day meme there’s a connection to beauty science. I thought it would be fun to talk about a couple of those today.

The color of love
Red is the color of love. It’s the color of valentines hearts, of lingerie, and of red lipstick. But you might be surprised to find that some of those sexy red lipstick colorants come from crushed bugs.

Chocolate and acne
You know candy is a popular Valentine’s Day gift but you really shouldn’t give chocolate to your loved one because it could make her face break out. Right? wrong! Well, right, sort of. 
This controversy has been raging back-and-forth for decades. Chocolate was originally thought to contribute to acne but initial studies indicated that there is no direct correlation. Then, in 2008, a group of Australian researchers put it to the test again. They had a group of panelists eat a sugary, starchy diet while the control group ate healthy. At the end of 8 weeks they had dermatologists examined the faces of the panelists (on blinded basis) and they found of those on the crappy diet had more acne breakouts. But even this study has not definitively put the question to rest. For one thing the diet wasn’t based on chocolate alone.

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Question of the week: are bar cleansers bad for skin?Soap_in_blue_dish

Mary Ellen says…I’ve heard bar cleansers are not good for our skin because the waxy ingredients that make the soap a bar cause plugged pores. Is this true?

Regular soap

When you’re talking about “regular” bars of soap I think the classic example that comes to mind is the old Ivory soap. Remember their advertising slogan: “So pure that it floats?” Of course the reason it floated had nothing to do with its purity. It was one of those accidental discoveries – somebondy left the mixer on too long and the soap became aerated so the air bubbles make it float. But it made for a memorable commercial.

There have been hundreds, if not thousands, of similar soap products since then but all true soaps have one defining characteristic in common: they are made by neutralizing a fatty acid with an alkali material. That’s what “soap” means. By the way, when the first laws regulating cosmetics were created back in the 1930s, the soapmakers managed to have soap excluded from law which is why you won’t see a list of ingredients on a true soap bar. If the ingredients were to be listed you’d see things like sodium cocoate or sodium tallowate.

Lye soap

One of the earliest forms of soap is lye soap. No it’s not called lye soap because the advertisers make dishonest claims about it, lye actually refers to the “alkali” material that’s used to neutralize the fatty acids.

According to legend, lye soap was discovered in ancient times when animal fat from cooked meat spilled into ashes from fire. When rainwater washed the mixture away they noticed that it created lather and they eventually figured out it could be used for cleaning. So the animal fats provided the fatty acids and the alkali was pot ash specifically potassium hydroxide. (Originally lye referred to potassium hydroxide which was made by soaking plant ashes which are rich in potassium carbonate in water to make but overtime has also come to include sodium hydroxide.)

Castile soap

Another type of soap is Castile soap. Remember how we said soaps are made with some sort of oily, fatty acid? Well Castile soap is made with one specific type of fatty acid which comes from olive oil. Originally this was produced in the Castile region of Spain, hence the name Castile soap.

Glycerin soap

I’m sure you’ve heard of glycerin soap. That’s a type of soap bar that’s clear because it’s made with glycerin, right? Wrong! All soap bars are made with glycerin because it’s part of the natural manufacturing process. When when the oils are reacted they split apart and release glycerin. In fact all glycerin used to be produced by soapmaking before we developed industrial processes of making it.

What most people refer to as glycerin soap is really just a gelled transparent soap bar. The reason it’s transparent is that it’s heated with sugar and alcohol which prevents the soap molecules from crystalizing so the bar stays clear. Take that, you disingenous glycerin soap bar manufacturers!

Synthetic Detergent bars (aka Syndet bars)

Enough about true soap bars not let’s talk about synthetic detergent bars. The difference is that instead of saponified fatty acids as the primary cleansing and foaming agents, these bars rely on synthetic detergents.

These are known as “cleansing bars” or “beauty bars” because by law they can’t be called soap. That’s part of the 1938 FD&C act that we talked about. But why would you want to use a synthetic detergent?

Because soap has a couple of serious drawbacks. First, if you have hard water the soap can react with the minerals in the water and form and in soluble residue. This used to be called bathtub ring and it was really a big problem. Not only could it mess up your bath tub but it could leave a film on your hair and skin that was really hard to rinse away. Most of our audience is probably too young to remember that because detergents have been in use for so long now. The second issue with soaps is that they have a high pH and are harsh on skin. We’ll talk more about that in a minute.

So as industrial chemical chemistry progressed in the 1940s synthetic detergents were developed and incorporated into cleansing bars. While there are many of these detergents in use, probably the most popular and best in terms of mildness and lathering is sodium cocyl isethionate. While detergents such as this are the primary active ingredient in modern cleansing bars they’re typically blended with true soaps like we’ve already discussed.

By the way, since these are not soaps they ARE subject to cosmetic labeling requirements. Therefore you will see a conventional ingredient list on the back of the package. See the show notes for an example ingredient list for a cleansing bar:

Sodium cocoyl isethionate, stearic acid, sodium tallowate, water, sodium isethionate, coconut acid, sodium stearate, sodium dodecyl benzene sulfonate, sodium cocoate, fragrance, sodiumchloride, titanium dioxide, trisodium EDTA, trisodium etidronate, BHT

Next let’s talk about how these different types of cleansing bar affect your skin.

Soap bars are harsher than detergent bars

There seems to be little question that true soap bars are more harsh than the synthetic detergent bars. That’s due to their pH as well as the nature of soap molecules. Multiple studies have proven that repeated use of soap bars can damage the skin by drying out the stratum corneum. It’s believed that soap damages the skin’s natural moisture barrier by binding to and denaturing of proteins in the stratum corneum. (Some detergents do this as well.)

For example, one test evaluated three types of cleansers. The first was a synthetic detergent bar using SCI, the second was a high glycerin TEA soap. And the third was a traditional soap based on the sodium salts of coconut oil and tallow. The degree of irritation and the amount of surfactant binding is consistently less with the SCI. Bars is based on true soaps are more binding and more irritating depending on exactly how they are blended.

But, setting the irritation issue aside for the moment how would we answer Mary Ellen’s questions about cleansing bars causing acne breakouts?

Do waxy ingredients plug your pores?

There’s a popular misconception that waxy ingredients clog pores. At face value this sounds reasonable – waxy ingredients get inside the little holes in your skin, the pore becomes plugged up and you develop acne. But that’s not what happens at all. Ingredients that contribute to acne trigger a condition called “retention hyperkeratosis” which means that dead skin cells become stuck inside the hair follicle. Excess sebum is a contributing factor to this condition. But this effect can occur with solid ingredients as well as liquid ingredients. So the “waxiness” of an ingredient really has nothing to do with how likely it is to cause acne. Regardless, once the follicle becomes plugged it turns into what is called a black head. The technical term for black head is a comedone which is where the term “comedogenic” comes from. Finally, if a certain type of baceria are present the plugged folicle can become infected and turn into a white head. And before you know it you have a pus filled pizza face. So how do we know which ingredients will cause this problem?

How to tell if your cleansing bar ingredients will cause breakouts

Unfortunately we don’t know for sure. There is a test called the Rabbit Ear Assay which is used to predict whether or not an ingredient will cause acne but there’s a lot of controversy over the accuracy of this method so at best consider this a rule of thumb test to rule out the worst offenders.

Also, not every single cleansing bar ingredient in the world has been put through this test so the effect of a lot of them are unknown.

And, to make things worse, combinations of ingredients can act differently than single ingredients so you really need to test a finished formula rather than just look at the comedogenicity rating of its individual ingredients.

So, the best we can do is point out a few ingredients that are known to be the worst offenders. If you want to know if a specific combination of ingredients has been put through this test the only way to know for sure is if the manufacturer has done the test and labels their product as non-comedogenic. But even then that’s no guarantee.

Ingredients to avoid

I don’t think any of the actual cleansing agents in either real soap bars or detergent bars show up on the list of acne causing ingredients. At least none of the published lists that I can find.

However, some of the other ingredients used in soaps in detergent bars are known to have a comedogenic potential.

The oils that are used to make soap may be comedogenic. For example: wheat germ oil is rated 5 which is highly comedogenic. Sesame oil is a 4 and olive oil is a 2 (which is moderately low.) That means I would expect Castile soap may be less likely to cause breakouts than some other oil based soaps.

Vegetable butters
Vegetable butters are are added as “super fatting” agents. That means there to counteract soaps drying effect on skin. Cocao butter and coconut butter are both rated “4” which is “fairly high” in comedogenicity.

These are the ingredients that are added to keep the cleansing bar from dissolving in the shower. They are typically fatty acids like stearic acid or fatty alcohols like cetyl alcohol as well as some waxes. Some of these do have comedogenic potential.

Other ingredients
Things misc. ingredients like certain red dyes, even fragrances have been shown to cause acne.
So the best we can suggest is to stay away from the few ingredients we have flagged here.

The Beauty Brains bottom line

First to be aware that what most people call “soap bars” are really synthetic detergent bars.

Second, true soap, while it is more natural, is harsher on skin. That’s partly because of the high pH and partly because of the way soap interacts with skins proteins.

Third, because of the ingredients that are added to super fat soap that you can be more likely to cause acne than detergent bars. check the show notes for some of the specific ingredients that we talked about.

And finally you can look for cleansing bars that are designed to be used on acne prone skin. At best this means the manufacturer has tested them for comedogenic city but even that does not guarantee it won’t cause breakouts for any given individual.

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      • Clever lies that the beauty companies tell you.
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      • Which ingredients are really scary and which ones are just scaremongering by the media to incite an irrational fear of chemicals.
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Comments on this entry are closed.

  • Michele February 11, 2015, 5:51 am

    if you only tested one kind of traditional soap that is coconut oil & tallow based & written off soap as damaging your scientific method leaves a lot to be desired.
    Handmade Soap makers spend a great deal of time formulating in order to find “the perfect” combination for their use: decorative bar, facial etc. Bars will also vary in mildness i.e. a Castile/bastile bar that has been aged 6/9 months maybe longer.

    • admin February 12, 2015, 8:49 am

      Our advice is not based on testing one type of traditional soap. We base our advice on scientific, controlled evidence.

    • Eileen February 12, 2015, 12:42 pm

      I’m going to respectfully play the devil’s advocate here and say I think you misread the section “Soap bars are harsher than detergent bars”. In that section the Brains state, “Multiple studies have proven that repeated use of soap bars can damage the skin by drying out the stratum corneum. . .” They then go on to say, “For example, one test evaluated three types of cleansers. . .” The operative words that you seemed to have missed are “multiple studies” and “for example”. The Brains aren’t basing their statements on the study of one soap as you have suggested. Rather, they are offering one study as an example of the multiple studies that have been conducted.

      Perhaps the Brains could have referenced some of those other studies. That way, you could have done your research before erroneously finding fault with their methodology.

      • Randy Schueller February 12, 2015, 2:57 pm

        Thanks Eileen. I couldn’t have said it better myself.

  • Eileen February 11, 2015, 10:45 am

    Wow! We’ve come a long way from boiling fat with ashes as the ancient Babylonians did–and thank heavens for that! 🙂 Thanks for all the information about a basic product that has been in use for thousands of years. I had to smile, though, when I read your comment that most of your readers were too young to remember soap scum bathtub ring. I remember the stuff all too well and used to hate the scum that would float on the surface of the water in a tub or sink and coat everything that came in contact with it. Yes, we’ve come a long way in the development of products we use to cleanse ourselves.

    • Randy Schueller February 11, 2015, 11:13 am

      Be careful Eileen, you might date yourself if you admit to remembering bathtub ring!

      • Eileen February 11, 2015, 3:56 pm

        Yeah, well at least I don’t remember boiling the fat with the ashes! LOL

  • Anna February 12, 2015, 7:10 am

    I do understand your chemical point of view, but I have to agree with Michele above. Since I started to use my own handmade soaps (superfatted and chockfull of glycerin, the by product of the saponification process and extracted from most commercial made bar soaps) 10 years ago my skin has become softer and smoother than ever before. How can that be, regarding to the supposed proteïn break down, the high pH and the damage done tot the natural moisture barrier of the skin??

    • admin February 12, 2015, 8:47 am

      That’s a good question Anna. We don’t give individualized advice but rather advice that is applicable to the majority of people. Your skin may have a high tolerance for the damage done by soap. It’s just your individual genetics. We base our conclusions on scientific evidence not the evidence of individuals. Just because soap doesn’t hurt one person’s skin doesn’t mean that it’s good advice for everyone to take. Count yourself lucky that your skin is unique compared to the majority of the population.

    • Ann Rein February 22, 2015, 11:15 am

      I agree with you, Anna. I’ve used goat’s milk, oatmeal and honey soap on my face for years now, I’m 58 (almost 59) and am constantly complimented on my skin. I had severe cystic acne as a teen, and tried so many things to ‘fix’ my face, dermatologist after dermatologist, prescriptions, over the counter, whatever, and good soap is what calmed my skin down. That’s why I started making soap, because of the benefits I saw for myself and now for others.

    • alex May 3, 2015, 6:23 pm

      Anna, your experience isn’t necessarily typical.

      I also developed a superfatty formula I loved. The soap’s lather felt rich, emollient, and for a true soap it was quite mild. After washing, I didn’t need as much lotion because of all the glycerin and lipids it left behind. I thought I finally had a soap I could use in the shower.

      Unfortunately, after using it regularly my skin became flaky and constantly irritated, leading to break outs. Since I have the same problem with other soaps and alkaline substances, my best guess is that soap’s high pH – no matter the soap – is a problem for me.

  • Clary February 12, 2015, 12:16 pm

    I rarely have breakouts and offer three secrets to friends: salicylic acid, hydroquinone and sunscreen. The cheap stuff. As in Wal-Mart cheap. I’ve tried many expensive brands but always go back to Biore, St. Ives peach scrub, whatever cheap brand of skin bleaching cream (hydroquinone) is available and Neutrogena oil free 100 SPF sunscreen. I’m 32 and have never needed botox. People always ask me what I use and are surprised it’s the inexpensive stuff 🙂 I swear by skin bleaching to even the skin tone, which makes you look younger. Would love to hear about some scientific studies as to its safety though!

    • Laura April 23, 2015, 11:44 am

      You’re 32; I sure hope that you would not have the need to be shooting up with Botox yet!

  • Eunice September 6, 2017, 2:38 am

    I have seen first hand how handcrafted soap damages the skin’s protective barrier. I am an Esthetician and I get to see people’s skin up close. I will say that people love the way true soap feels on their skin but it doesn’t mean it’s good for you. People with thicker skin don’t usually notice or feel the damage but in time you WILL see it. I honestly don’t think people will stop using it. It’s cheaper and can be made at home.

    • Jen January 13, 2018, 8:48 pm

      I don’t know if I’ve ever come across “true soap,” and I’m intrigued by your comment that people like the feel of it… Is it the lather? Anyway, sounds like it’s not great for skin, so I won’t go looking for samples! And are people really making soap for personal use?? Why, for cryin’ out loud?!