What Are Syndets?

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What is a Syndet Soap or Shampoo Bar?


In October, 2015 I wrote a blog titled, "What is pH Balanced Skin Care?" In that blog there is a detailed discussion about the thoughts that I have concerning syndets and the idea pH balanced skin cleansing.

However, in the last few months we have received some emails asking if we would make "natural" syndet soap and shampoo bars. At that point, I began to realize that people did not understand the definition of a "syndet." Why?

Because there is no such thing as a "natural" syndet.


What is a Syndet?

Natural Organic Aromatherapy Lavender SoapSyndet is a blended word made by combining the words “synthetic” and "detergent." It is the name given to a cleansing bar or liquid made by the binding of synthetic detergents.

Detergents are surfactants. Surfactants are used in cleansing products to reduce the surface tension of water so that the water can combine with oily dirt and wash it away.

Learn More Blog: How Does Soap Work?

The detergents (surfactants) used in syndets generally come from the sulphate family and are derived from natural oils, fats, or petroleum products.

Any cleansing product that foams, lathers, bubbles and cleans contains a surfactant. Soap is a natural surfactant, while detergents are synthetic.

If the cleansing product you are using on your body or hair is labeled "soap-free" or "sulfate-free" it is still using some type of synthetic detergent as a lathering agent.

The word "syndet" bar sounds much better than a "synthetic detergent" bar and is more attractive to consumers who tend to shy away from synthetic skin care.

Although the word syndet may be new to many people, the first syndet bar, Dove, was introduced in 1955.


Syndets vs Natural Soap?

Syndets Soaps & Shampoos are Made with Synthetic DetergentsSyndet bars are labeled and marketed with words like, “cleansing bar,” "body bar," or “beauty bar.”

These bars cannot call themselves "soap," because the word "Soap" has a legal definition provided by the FDA. Since syndets are made with synthetic surfactants they do not meet the legal definition of soap.

There is a lot of buzz about using pH-balanced syndet bars to go "soap-free." The theory is that since they are less alkaline than natural soap these synthetic detergent bars will not harm the acid mantle.

Real handmade soaps, made with natural ingredients, have an alkaline pH that varies from 8 to 10 depending on how they are made.

The problem -- you will be trading your natural soap for synthetic detergents.

The synthetic detergent bars may have a pH that is more acidic than handmade natural soaps, but many people are not only sensitive to detergents but are also sensitive to the preservatives, synthetic colors, and fragrances used in the non-soap bars. These synthetic detergents and other ingredients will also be washed down the drain where they can enter our waterways.

While Syndet bars may have a neutral or slightly acidic pH, they are still cleansing agents that will dissolve the natural protective oil layer on our skin as they clean.


Why Are People Asking for Syndet "Soap" and Shampoo Bars?

Natural Organic Herbal Shampoo BarAs consumers demand more and more natural and organic personal care products, a marketing war has developed between commercial and natural companies concerning pH balance skin care.

People are asking for syndet soaps because they have been told that need pH balanced skin cleansers.

People are asking for syndet shampoo bars because they have been told that they work much better than soap-based shampoo bars.

As I said above, any product that creates lather in order to cleanse the skin or hair needs a surfactant and soap is a natural surfactant.

Therefore if a shampoo bar claims to be "soap-free" there must be a synthetic ingredient acting as a surfactant or detergent to create lather and cleanse hair.

Syndet bars are made with many of the same ingredients and detergents as the liquid shampoos that people love, only without the water and plastic bottle. They usually create a lot of foamy lather and come in fun colors and scents.

So, if your hair is used to bottled detergent shampoo, it may be easer to adjust to syndet shampoo bars because they clean with similar detergents and rinse clean like detergents even in hard water.

Many of the new shampoo bars, marketed by the more "natural" companies have traded harsh surfactants like Sodium Lauryl Sulfate for Sodium Coco Sulfate or Sodium Cocoyl Isethionate which are derived from coconut or palm oils.


Are pH Balanced Syndets Better For Your Skin

Baby Toddler Washing Hands with Natural SoapA study published in Dermatology 1997;195:258–262 concluded that all skin cleansing agents, even normal tap water (with a pH of 7), influence the acid mantle of the skin.

The purpose of a skin cleanser, whether it is pH balanced or not, is to get rid of the oily layer that holds the dirt and contaminants to your skin.

So, while pH-balanced syndets have a neutral or slightly acidic pH, they are still cleansing agents designed to remove oils.

Sebum (natural skin oil) makes up an important component of the acid mantle, removing this fatty layer may make us feel clean, but aren't these fats an important part of our natural acid mantle protection?

Commercial skincare companies like to place all of the blame on skincare products that are not pH balanced.

However, the pH value alone does not determine whether a product is gentle, harsh, or even effective. There are so many factors that contribute to the overall health of the skin that if you focus simply on pH you will neglect other factors that are just as important or even more important than pH.

The synthetic detergents and other synthetic chemicals used in syndet cleansing bars, liquids, shampoos to make them "pH balanced" – can be irritating or even damaging to the skin.

OK, I know that I am a natural soapmaker and perhaps just a bit biased in favor of natural soap. But since the internet is teeming with articles that are anti-soap, I felt I needed to do some research.

Most of the websites that talk about skin pH are not science-based sites. They are beauty blogs, women’s magazines and commercial sites selling “pH balanced” skin and hair products.


My Research Questions

Natural Skin Care The Acid MantleMost of the research I reviewed agreed that real soap did elevate skin pH slightly more than syndet bars, but I was looking to find some research that would answer a few more questions:

  • How is the acid mantle affected by cleansing?
  • How much of a change is there in pH when using real natural soap versus a synthetic detergent bar?
  • Are there any long-term effects on skin pH from using a natural soap bar?
  • Does natural soap affect skin hydration more than a syndet bar?
  • All soaps are not the same and likewise, all syndets are not the same. So is it only the pH that affects the acid mantle and skin irritation?

There is research on both sides, but here is what I discovered pertaining to my questions:

  • Healthy skin will regain its acid mantle within 15 to 30 minutes and problems with the acid mantle are only of concern in if there is a compromised skin barrier. (Dr. Zoe Draelos: "Dermatology" April 1, 2011).

  • Another study compared 6 different types of cleansers varying from very alkaline to very acidic. The study found the following
    • (1) there was a slight increase in pH with the alkaline soaps
    • (2) all products had a drying effect on stratum corneum (the outer layer of the skin), but soaps that were superfatted had less
    • (3) TEWL (transepidermal water loss) measurements showed little change between natural soap and a syndet bar
    • (4) all changes were completely reversible and all values returned to normal within 90 minutes after washing
    • Source: Mirela Moldovan and Alina Nanu. “Influence Of Cleansing Product Type On Several Skin Parameters After Single Use.” Farmacia, 2010, Vol. 58, 1

  • Skin pH rises 1.1 points following washing with water alone, 1.2 points after washing with alkaline soap and 0.98 points after washing with a synthetic detergent beauty bar. (Takagi, Y., et. al. [2014], "The Long-Term Use of Soap Does Not Affect the pH-Maintenance Mechanism of Human Skin" in Skin Research and Technology)

  • Some say that the long-term use of alkaline soaps causes irreversible damage to the acid mantle. A study was done on two groups of people; one group used regular soap (pH about 10) and the second group used an acidic cleanser--each for 5 years. The study concluded that long-term continuous use of real soap does not affect the ability of the acid mantle to maintain the normal mildly acidic pH of the skin. (Takagi, Y., et. al. [2014], "The Long-Term Use of Soap Does Not Affect the pH-Maintenance Mechanism of Human Skin" in Skin Research and Technology)

  • Some believe that regular soap removes the natural oils from the surface of the skin and decreases skin hydration. To test this, a study compared the skin of babies washed with water, a mild acidic cleanser and normal alkaline soap. All three cleansers, including water, decreased the natural skin oils and increased pH. However, there were no differences in skin hydration. So basically, everything affects the acid mantle, even water. (Gfatter, R., P. Hackl, and F. Braun, 1997, Effects of soap and detergents on skin surface pH, stratum corneum hydration and fat content in infants: Dermatology, v. 195, p. 258-62.)

  • Syndets, which are not all the same and vary widely in terms of their chemical structure and skin compatibility, are not necessarily less irritating than soaps. A study done testing the "irritation potential" of syndets and soaps with various pH numbers, seems to show that it is something more than simply a pH number that causes skin irritation. The study discovered the following:
    • the least irritating syndet was Dove White, with a pH of 7.53
    • the most irritating syndet was Avecycle, with a pH of 4.61
    • the least irritating soap was Johnson’s Baby Oat, which had a pH of 12.35
    • the most irritating soap was Camay Gala, with a pH of 9.36
    • Source: Abbas, S., Goldberg, J.W. and Massaro, M. [2004], Personal Cleanser Technology and Clinical Performance. Dermatologic Therapy, 17: 36-38

So according to this study the least irritating soap had the highest pH and the syndet with the higher pH was less irritating than the syndet with a lower pH.

While I found these and other studies interesting, they left me with even more questions.
  • What does pH-balanced actually mean? We know that the pH level of the acid mantle varies from person to person. We also know that there are many factors that influence that pH. I guess the question we should ask is, pH balanced to what and for whom?

  • Several websites talk about the “ideal skin pH." But we are all unique with different skin types. So again I ask, "ideal for whom?"

  • There are so many external and internal factors that can affect the pH of the acid mantle, how are these variables being controlled in all of these studies? Let's say that I do not have an ideal skin pH (whatever that means) and I have wrinkles. Are my wrinkles only caused by the pH of my acid mantle or perhaps it is also my age, my genetics, where I live, what I eat, how much time I spend in the sun, the medications I take, etc.

I absolutely believe that we need a healthy, intact acid mantle, but if your skin is healthy and you use a slightly alkaline cleanser, your skin will quickly revert back to its normal pH. It is way too simplistic to blame every skin care problem on products that are not pH balanced. Is all this hype concerning skin pH really about the science of skin care or selling products?



It is also important to remember that . . . all soap bars are not created equal!

Natural Organic Goat Milk Oatmeal SoapOne question I was not able to answer was, "What 'soaps' were being studied in the research when comparing soap to syndets?

I found so many articles about the evils of soap that began with the words, "Using a harsh bar soap with a high pH"... So, what is the "harsh bar soap? Also, since pH can only be measured in water-based liquids, how are they measuring the pH of a solid bar of soap?

    Poorly quality handmade soaps and mass-market commercial soaps often contain free Alkali which increases the pH and makes them harsh and drying to the skin. Allowing there to be some leftover alkali in the soap increases the shelf life and hardness of the soap bars, which is important when a bar needs to sit on a store shelf for years.

    Commercial companies often remove the natural glycerin and add synthetic ingredients not found in natural soap, such as synthetic colors or scents and chemical preservatives that increase shelf life.

    The chemical composition of the new syndet "non-soap" bars and liquids varies from syndet to syndet. Many companies have touted how they have moved away from harsh synthetic detergents, like sodium lauryl sulfate (SLS), to milder synthetic detergents.

    While that may sound like a good solution, how long did it take to discover that SLS and other additives were harmful? How long will it take to discover that these newer, milder synthetic detergents are also harmful to our skin, our bodies, and our environment?



    The most accurate test of a good mild soap is how it feels on your skin. Your body will balance the skin pH on its own. So, listen to your skin and trust it.

    We have received many emails, phone calls, and testimonials from people who have seen dramatic changes in their skin after just a few days of using our handmade soaps and shampoos.

    They have switched from their “pH balanced” synthetic "soap," body wash, or shampoo and are finally free from itching, dry skin, eczema, and other skin and scalp problems.


    NOTE: I just want to mention another type of cleanser called a combar or combination bar. Although this word is not used much in the US, it is basically part soap and part syndet. When you see ingredients that contain words like sodium palmate (a soap surfactant) along with Sodium cocoyl isethionate (a synthetic surfactant) you are really looking at a combar! Many of the bars that we call syndets, like Dove, are really combars.


    Natural Skin Care Blogs

    The War on Natural Soap!

    What is pH Balanced Skin Care?

    Sodium Coco Sulfate: Is It Natural?

    Are All Handmade Soaps The Same?

    12 Reasons To Use Natural Soap



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