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Is soap bad for skin?

Anne says…Real soap is NOT problematic for all people, either on skin or on hair. Many just don’t like the feeling on hair, but if you happen to, just use shampoo every few washes to prevent buildup. And as for skin, many people have zero problem with a high pH wash off product. For those who do, there are other options yes. Sad to see this answer jump onto the bandwagon of disregarding soap without a full answer, and it just isn’t the whole truth to say that “Regular soap is not good for skin”.

The Beauty Brains respond: 

Anne’s comment comes to us from our recent post on using bar soap on hair. I agree that my original answer wasn’t detailed enough so I’ll try to correct that here.

I certainly don’t blame Anne for defending bar soap since she’s affiliated with Dot & Lil, a company which sells vegetable oil based soaps. But it’s well documented that soap is more drying to skin than surfactants. In fact, plain old ivory soap is used to dry out skin in moisturization testing!

Soaps and synthetic surfactants can dry skin

Of course that’s not to say that surfactants are perfect and that they do no harm. Anything which solubilizes oils has the potential for stripping the skin. Some surfactants, like sodium lauryl sulfate, don’t rinse well because they can interact with skin protein. The residue they leave behind is irritating so some people.

BUT, surfactants (which typically have a pH in the range of 5-7) do not upset the skin’s acid mantle as much soap which has a pH in the range of 9-10. If the mantle is washed away or neutralized by alkaline agents then the skin is more easily damaged or infected. That’s because, without the mantle, the skin cells start to separate and allow more moisture loss which in turn causes tiny cracks in the skin where bacteria can enter.  Once the mantle is depleted and the pH of skin gets above 6.5 you’re much more prone to damage and infection.

There are number of studies such (see below) that have evaluated the harshness of cleansers and have consistently found that soap is worse than surfactants.

The Beauty Brains bottom line

All cleansers have the potential to strip oils from your skin but soap has been shown to be more drying, harsher, and more disruptive to the skin’s protective acid mantle than many surfactants.


Interactions of cleansing bars with stratum corneum proteins
Journal of the Society of Cosmetic Chemistry 46, 301-320 November/December 1995)

Forearm wash test to evaluate the clinical mildness of cleansing products
Journal of the Society of Cosmetic Chemistry 39, 355-366 (November/December 1988)

Soap and detergent bar rinsability
Journal of the Society of Cosmetic Chemistry 37, 89-97 (March/April 1986)

{ 26 comments… add one }

  • Eileen May 12, 2014, 11:42 am

    Soap recipes have been found that date back more than 4,200 years, but just because they worked for the ancient Babylonians, it doesn’t mean that they are what we should be using today. Over the millennia, those ancient soap formulas evolved as people sought to create a better product that was easy to use, convenient to store, pleasing to the senses, and that would do the job of thoroughly cleansing without being harsh and drying. Eventually, we arrive at today’s bar soaps which are much less harsh than the primitive soaps of yore or even the ones of the past few decades, but they definitely aren’t the gentlest, most skin/hair friendly products around. That’s been proven time and time again in the lab and, if store shelves are any indication, most consumers are showing a strong preference for other skin cleansers over bar soap. The way I see it, abandoning bar soap in favor of other surfactants is just another step in the evolution of cleansers as we search for a better means of caring for our skin and hair.

  • Laurie Brown May 12, 2014, 11:54 am

    I like to use a true soap on my face, *but* my face and neck are very oily. It works perfectly for me, whereas if I use a syndet my face is shiny in no time and my makeup doesn’t stay put nearly as well. I suspect the soap/syndet thing is a case of YMMV.

  • Pedro May 12, 2014, 1:32 pm

    Out of curious, in Japan a facial cleanser that isn’t soap based (in fact, they usually are mixture of synthetic surfactants and soap) wouldn’t sell almost any there. Due to cultural reasons a facial cleanser there must make an extremely dense and huge foam – something impossible to achieve just with synthetic surfactants). Some companies even disclosure the density of the foam in microns. LOL On the other hand, they also usually contain a lot of anti-drying ingredients and people use them without to put almost any pressure during the massage with the foam. The foam is made on the hands and then applied very gently on the facial skin. I think it helps…

  • Jtest11 May 13, 2014, 2:44 am

    Interesting, been recently looking for the perfect price/performance bar or body wash.

    Most bars dry me out like crazy (especially Dove for some reason) and most washes leave an annoying film. Recently stumbled upon Old Spice’s body washes and they seem to be the only wash I can find that are simple cleansers:

    Water, Sodium Laureth Sulfate, Sodium Chloride, Sodium Lauryl Sulfate, Fragrance, Cocamidopropyl Betaine, Sodium Benzoate, Citric Acid, Disodium EDTA, Methylchloroisothiazolinone, Methylisothiazolinone, Potassium Sorbate, Yellow 5, Red 33

    Thinking I’m just gonna stick with them as a body wash/shampoo and use another moisturizer post-shower.

  • Anne May 13, 2014, 9:06 am

    Thank you for the response to my comment Perry! This is a much fuller picture. I always make sure to tell people to stick with syndets if that is what works for them. The thing is, most people do not distinguish between the two in bar form, and even more so with bars that have a mix of true soap AND syndets. Understandably it is a confusing distinction for most consumers! Add to that that handmade and handcrafted bars are not at all like most commercial bars, and it gets even more blurred. The fact that many handmade soaps are superfatted, etc. means they are unlikely to perform like the ones you have presented research for. Though again, there will ALWAYS be people who do better with a low PH syndet bar, and also those who do best to avoid foaming cleansers of all kinds, true soap or not. As a manufacturer of both bar soaps and other skincare items I spend a lot of time thinking and talking about this of course, and mainly I just think people need the correct info to make a decision. It just gets under my skin (ha!) to see bar soap presented as a non-option–and lest we forget, not all bar soap is created equal! Thanks for taking the time to present this well, I am happy to read it!



  • Natasha May 13, 2014, 11:13 am

    I just read the 1988 study, as a chemist myself, I found the procedure very well thought but the formulation of the soaps are not comparable (with and without synthetic surfactants), there is not a test with the same formulation (Tallow/coconut oil) with and without surfactant. It is well know that coconut oil soap is very dryer to the skin, so I was not surprised by the results, that is why it is not recommend to use over a 30% of it in a handcrafted soap. I would agree with Anne in this, not all the soaps are made equal and for someone that is looking for a real soap (with not surfactants added and glycerol still on it) a well formulated handcrafted soap could be a good alternative. Also I would not consider this paper coming from Procter and Gamble an “independent study”. Just my two cents.

  • Rachel July 7, 2014, 10:42 am

    Does tea work to cleanse hair?

    • Randy Schueller July 7, 2014, 7:27 pm

      No. (Other than the fact that tea is dissolved in water and water will rinse way dirt.)

  • Kaylee Jayne March 5, 2015, 5:21 pm

    Hi there,

    I totally understand the science of this (the pH, the acid mantle, etc.), but I’m one of those people that has skin success with a higher-pH true soap. What would be the scientific reasoning behind people like me? I’ve been searching the internet but I can’t find an answer. I thought maybe you guys would know.


    • Randy Schueller March 5, 2015, 8:12 pm

      Hi Kaylee. It’s hard to say why you like “true” soap so much. What else have you tried? (For example, have you used the syndet bars we talked about based on SCI? Or body washes based on mild surfactants?) And, what kind of “skin success” have you had? (Cleaner feeling skin? Fewer breakouts? Less dryness? etc etc.)

      • Kaylee Jayne March 11, 2015, 11:35 am

        Hi Randy! I’ve tried Dove body wash, and Bath and Body Works body wash, and some other random things I’d pick up at the store (but we usually have the Dove Deep Moisture something-or-other in the shower, because it’s what my husband likes). When I use it, I usually feel dry (my legs get extra flakey) but also slimy (mostly on my back) at the same time, in a way that I don’t feel when I’m using a bar of the old timey stuff. I guess I just don’t get dry with soap in a way that I’d expect. Could it be our soft water?

        As for my face (which I consider a completely different animal), I like a “milky” kind of cleanser (smooth skin, no breakouts, no dryness), but pH tested over an 8 (maybe even close to a 9!). I thought I probably shouldn’t use it anymore because of the pH and I recently tried a mildly acidic cleanser but broke out on my temples and nose, got uneven skin tone, and really dry skin around my mouth. I stuck with it for two weeks, then gave up. (I also tried the oil cleansing method with even worse pimples.)

        I guess my ultimate question is, should I stop using these products because of the high pH? After the additional reading I’ve done on the internet in the last couple of days, it sounds like I’m irreparably damaging my skin and even though it feels and looks fine now, I’ll wake up one day with terrible wrinkles and spots and get infections. What should I do?


      • Kaylee March 11, 2015, 11:51 am

        PS: I just found the ingredients for the Dove my husband uses — it has SLS in it, not SCI. So now I’m not sure if I’ve tried an SCI body wash. Maybe I should look for one of those to try.

        • Randy Schueller March 11, 2015, 12:50 pm

          Yes, looking for and SCI product sounds like a good next step. The pH won’t be so high either.

          • Kaylee Jayne March 11, 2015, 1:00 pm

            Sounds like a plan!

            How about for my face? The cleanser I like is SLS-free. Can I keep using it even though it’s not acidic?

            Thank goodness for this website! I was really falling down the rabbit hole out there.

          • Randy Schueller March 11, 2015, 4:41 pm

            Can you send me a link to the product’s ingredient list?

          • Kaylee Jayne March 11, 2015, 5:08 pm
          • Randy Schueller March 11, 2015, 5:16 pm

            This looks like a fairly standard emulsion type oil cleanser. Are you telling me that the pH of this product is almost 9? Are you sure about that measurement? That result seems really strange because this kind of emulsion system is typical closer to a neutral pH of 7-ish.

            BTW, here are the ingredients for anyone who’s interested:
            Aloe Barbadensis Leaf Juice(1), Aqua (Water), Stearic Acid, Glycerin, Glyceryl Stearate SE, Cetearyl Alcohol, Cetyl Alcohol, Caprylic/ Capric Triglyceride, Helianthus Annuus (Sunflower) Seed Oil(1), Aleurites Moluccana Seed Oil, Borago Officinalis Seed Oil(1), Butyrospermum Parkii (Shea Butter)(1), Citrus Aurantium Bergamia (Bergamot) Fruit Oil, Citrus Aurantium Dulcis (Orange) Peel Oil, Citrus Limon (Lemon) Peel Oil, Hydrogenated Palm Kernel Oil, Arnica Montana Flower Extract(1), Camellia Sinensis Leaf Extract(1), Chamomilla Recutita (Matricaria) Flower Extract(1), Citrus Limon (Lemon) Peel Extract*, Laminaria Digitata Extract(1), Lavandula Angustifolia (Lavender) Flower/Leaf/Stem Extract(1), Linum Usitatissimum (Linseed) Seed Extract(1), Olea Europaea (Olive) Leaf Extract(1), Ascorbic Acid, Ascorbyl Glucoside, Cetearyl Glucoside, Potassium Hydroxide, Tocopheryl Acetate, Xanthan Gum, Alcohol(1) , Benzyl Alcohol, Potassium Sorbate, Sodium Benzoate, Limonene

          • Kaylee Jayne March 11, 2015, 5:36 pm

            Hmm. Maybe because I tested it with water? (I tested the my hands when I washing my face.) The green just looked a littler darker than the “8” to me.

            Anyway, I can keep using it, yes? 🙂

          • Randy Schueller March 12, 2015, 6:38 am

            If you like the way it makes your skin feel then it should be fine.

  • Kathleen July 13, 2015, 8:22 am

    I have had acne, black heads and just aweful skin for the last 30 years. I tried all those PH balanced cleaners, all the acne care thingies, but nothing changed it. I switched to a bentonite clay natural soap bar, and POOF, it all went away! After 30 years of yucky and low self estime, I feel good about myself, and I will never switch back.

  • Elsa July 30, 2015, 11:29 pm

    Truly Natural soaps are not bad for your skin , as someone who has been using only soap on there skin all there life i can tell you soaps that contain nasty chemicals such as SLS and Alcohols are bad for your skin and they overly strip skin of important oils. As an eczema suffer i was looking for a solution to my skin problems and i did not want to give up my soap bar, after doing some research i came across a company called beauty and the bees http://www.beebeauty.com/ who make soaps 100 % chemical free and boy let me tell you don’t give up on soap until you try a natural soap bar the one i used from beauty and the bees was called Dead sea mud and leather wood honey it cured my ezcema and makes my skin smooth and even helped reduce my fine lines!! and just remember one last thing no real soap can not be made without lye and i know that word can seem scary but no lye remains in the final product so you have nothing to worry about.

    • Randy Schueller July 31, 2015, 7:26 am

      So how do you explain the scientific data that shows the higher pH of soap causes the natural acid mantle of the skin to take longer to recover?

  • Julia February 28, 2017, 1:46 pm

    I’m also one of the sucessful soap users and also wonder why it works so well even if it’s supposed to dry out your skin. I’m especially surprised because after washing my hair with soap (mosty babassuoil, sheabutter, avocadooil and natron in these) I don’t need to wash it for about 4 days and it doesn’t itches while I got dandruff and itching from most shampoos and my hair gets greasy after one to two days after every shampoo I’ve tried. Isn’t it supposed to be the way that if your hair gets greasy faster you’re using something that dries your skin more so the skin tries to moisturise itself or did I get something wrong?

  • Melissa April 16, 2018, 8:15 pm

    I make my own soap and have never ph tested any of them. It never really occurred to me that I would have a problem. And I don’t. My skin has never been happier than using my homemade soap and some jojoba oil. Fewer breakouts, more moisturized skin. I don’t have anything that isn’t healing because of a damaged acid mantle. All my family wants soap all the time because their skin does well with it too. I do have problems with really dry, tight skin though, when I do use a body wash. I’m sure it’s just a matter of preference.

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