What is the difference between a soap-based shampoo bar and a syndet shampoo bar?

What is the difference between a soap-based shampoo bar and a syndet shampoo bar?

We're glad you asked, there are huge differences between the two. On the core level they are different in two ways; ingredients and how they work. 

In short, soap-based are made from natural oils whereas syndet bars are basically solidified liquid shampoo. They each serve different purposes and we're going to give you the lowdown on how to find the best shampoo bar for you.

What is a syndet shampoo bar?

 The word is derived from the words synthetic and detergent and that's essentially what it means. They use detergents to clean your hair and are not as natural as they may seem. The type of detergents/surfactants that they use generally come from the sulphate family. We know there are such ingredients like sodium cocoyl isethionate, sodium lauryl sulphate, sodium lauryl sulfoacetate.
The first on the list is based on 'cocoyl' is derived from coconut oil and can be labelled as a natural product but it is chemically formulated. That being said, its the best of the bunch and the most gentle on your skin. You'll find it in a variety of personal care products including baby products. 
Sulphates are fabulous at helping you to achieve that clean feeling and are able to draw out dirt and oils from your hair. However, the downside to using sulphates is they can be highly irritable to sensitive skin. They're also being targeted as hormone/endocrine disruptors, which could have adverse changes to your health.
That being said, syndet shampoo bars will come with a lower or are pH neutral, as chemicals are required to achieve this outcome. 
As mentioned earlier, syndet shampoo bars are commercially available or salon-quality ingredients solidified into a bar form. They are the best option for those who are unable to achieve the desired effects from natural bars as they will be able to cut through highly mineralised water and cleanse your scalp free from dirt and oils. That being said, you will almost always need to follow with a conditioner as your scalp will be stripped of precious sebum by the sulphates. Often you will feel that your hair is left feeling like straw. 

What makes soap-based shampoo bars so different?

The best thing about soap-based shampoo bars is that they are made from all-natural oils like coconut, olive and castor. They also have the lovely scents of essential oils like lemon, lavender, rose, the list goes on. They are the most natural offering that you can get in a shampoo bar form. 
When creating a soap-based shampoo bar, soap makers can make bars via the cold-press or via hot-press methods. Cold-pressed bars like Solibar take longer to make and generally appear smooth when set. Whereas hot-pressed shampoo bars are quicker to solidify and will likely appear more textured in appearance.
What is similar is that both processes require sodium hydroxide/caustic soda/lye to solidify the oils into a bar. This process is called saponification and the great thing is that when done correctly all of the sodium hydroxide is used up in the process. So the end result does not technically contain sodium hydroxide, it’s just a part of the solidification process. Bars that do not contain sodium hydroxide are not soap but a detergent, hence syndet-based bars. 
The other important thing to consider when making the switch to a natural soap-based shampoo bar is that your hair is likely to experience a period of transition. We refer to it as the ‘transition phase’. (You can read more about it here). During the transition phase, your hair will simply move through a breakup from your old shampoo. We now know that several factors make change the timeframe in which you might experience transition, one of these factors is previous chemical buildup. There is one bad guy, in particular, and that is hard to remove and it’s called silicone. Silicone is essentially alike plastic wrap for your hair and can not be removed easily with the gentle ingredients in soap-based bars. You will need to use a clarifying shampoo to remove product buildup prior to moving to natural haircare. The lucky thing is we’re sending out clarifying shampoo sachets with every first order so that you can really get to the benefits of healthy haircare as quickly as possible. (More about how to spot a silicone here.)
The very best thing about soap-based shampoo bars is that without the nasty detergents in syndet bars, they are very gentle. So gentle in fact, that they clean your hair in a totally different way. Solibars rely on your hair to return to its normal function of regulating its sebum production in order to clean your hair in its natural form. It's also why some people can get longer periods between washing and also why we can be aligned with the No-Poo Method. We’ve written extensively on how this works here.
Given that soap-based bars do not contain sulphates or any other vicious strippers, you may or may not even need to use a conditioner. We have however made two different conditioner bars for those who need a little extra moisture - one is called Appley Ever After and the other is the partner in crime to our blonde Solibar called Blonde Way Or Another conditioner bar. You can check them out here. 
When we decided to create the Solibar there were a few things that we needed to make sure we had.
  • We wanted to be made from natural ingredients.
  • We wanted to be Vegan.
  • We wanted to have the least impact on the environment as possible, including packaging.
Whilst we understand that making the switch to natural haircare might not be for everyone, we’ve created a Facebook group called The Solibar Society to help you move through the transition as quickly as possible and to get access to all the latest tricks and tips of natural haircare. We’ve also got some incredible success stories shared by our members. Join The Solibar Society here.  
We’ve also put together some things to look for when selecting the right shampoo/conditioner bar for your hair. 
What to look for in a great shampoo bar:
🌿 Natural ingredients. 
🌿 Sustainable and ethical ingredients. 
🌿 Eco-friendly packaging and shipping.
🌿 No sulphates, parabens or other skin irritants or hormone disrupters.
🌿 No palm oil or palm oil derivatives. 
If you would like to check out what members from our Solibar Society are saying about Solibar, please head to the reviews section on our website - here. 
If you’re still confused on which Solibar is the best for you, please check out this page - Which Solibar is for me?
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