Differences between solid shampoos

Solid shampoo is becoming more popular and accessible. But it is easy to get lost and difficult to understand if it is really “natural” and effective. In this blog post I would like to share the information on how to understand and read the labels of solid shampoos and what are the main differences between various kinds you can find on the market.

/ pH balanced shampoo bars made with surfactants /

Saponified oils or surfactant based?

Dygo used to make shampoo soap, which was made from saponified oil, the same as soaps, just with a different composition of oils. These types of shampoo have a slightly basic pH (around 8-10) and it is recommended to do a vinegar rinse after washing the hair to bring the pH down. Our hair and scalp have a slightly acidic pH around 4.5-5.5, that is why shampoo soap is not a perfect solution for all hair types and can cause dry, sticky, itchy scalp or greasy hair.

/ shampoo soaps made with saponified oils /

Apart from simple soap, there are other surfactants, produced with more complicated processes, that have a lower pH and are gentler than saponified oils. We refer to them as “surfactants” to distinguish them from simple soap (which is also a surfactant).  Shampoo bars made with these surfactants have a pH more similar to that of our hair and scalp, and cleanse more gently. You do not need a vinegar rinse or transition period when using surfactant based shampoo bars. To understand if a shampoo bar is made as a soap or with surfactants it is important to memorise the two different types of ingredients. Saponified oils are called with two words, where the first word is always sodium, for example sodium olivate (saponified Olive oil), sodium cocoate (saponified Coconut oil). “Sodium” and the “-ate” suffix indicate that the recipe includes saponified oils and has a high pH. The most common surfactants used in shampoos are Sodium Cocoyl Isethionate (SCI), Sodium lauryl sulphate (SLS), Sodium Lauryl Sulfoacetate (SLSA), Cocamidopropyl betaine, Sodium coco sulphate (SCS), Decyl glucoside and others.

The problem with solid shampoos is that they often can be formulated with ingredients which are far from meeting the definition of “natural” and often include ingredients mostly derived from palm oil, such as cetyl or cetearyl alcohol, Sodium lauryl sulphate (SLS), Lauryl glucoside, BTMS-50, BTMS-25 and etc.

You also can find solid shampoo bars which are called 2in1 and also have a conditioner function. This type of shampoo bars are often made by combining different types of surfactants and adding other conditioning ingredients, commonly Behentrimonium Methosulfate (BTMS), which itself is derived from rapeseed oil, but pretty much always is sold already mixed with cetyl alcohol (palm oil derived). BTMS is also probably not fully biodegradable. I am not going to make lists of what ingredients to take away when choosing solid shampoo bars, but I invite you to familiarize yourself with the ingredients and make your own judgment.

Dygo has always had a commitment to formulate the most simple and close to nature recipes, that is why it took some time to start using more chemically processed ingredients. However, the effectiveness, high concentration, long lasting, zero plastic packaging of this type of shampoo bars creates a really great alternative to conventional shampoo, which consist 80% of water. Solid shampoo bars also allow a smoother transition from conventional shampoo than shampoo soaps.

The base of Dygo shampoo bars is Sodium cocoyl isethionate, which is derived from coconut oil, is 100% biodegradable and is very mild. The rest consists of plant powders, clays, vegetable oils, corn starch, horsetail tea and active hair nurturing additives, such as panthenol, rice protein and glycerine. We prefer that our shampoo bars have some cracks or other visual imperfections rather than compromising our fundamental beliefs by using palm oil derived, non biodegradable or petroleum derived ingredients.

/ Sodium Cocoyl Isethionate (SCI) /

Surfactant based shampoo making process / video by Giovanni Brajato /


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