Shampoo bars. Yes? No? Or It's not that Simple? - The Soap Coach
Shampoo bars yes or no

What exactly is a shampoo bar? Are there different kinds? Why am I struggling with my shampoo bar? How can I make a shampoo bar work for me? Are there plastic free alternatives to a shampoo bar?

Quite honestly the questions around shampoo bars are endless and it is also a very hot topic with what appears to be a pretty even split of supporters and protestors. What I have picked up on however, is that the protestors would love to be supporters, they just struggle with making the switch for a variety of reasons.

I get asked about them all the time in my workshops and I know they are the cause of many a heated discussion so it seemed to be a really great subject to write about.

What is a shampoo bar and are there different kinds?

We can all identify with the basics of what a shampoo bar is  - namely a solid which we can apply to our hair and which cleanses it. The current popularity, on the whole, arises from our desire to reduce our use of plastic and often because we believe it to be more natural and therefore better for us, our hair and the environment.

What many people will not realise however is that there are 2 distinct kinds of shampoo bar, soap based and detergent based, both of which are very different although they fulfill the same purpose.

Soap based bars are just that - defined as soap due to the way they are made and the presence of natural butters, oils  and sodium hydroxide in the initial ingredients. They are more often than not created using the traditional cold process method of soap making and will have a PH of around 10 as a result.

Detergent based bars are also known as syndet bars and are often sold or advertised as soap free. They will be made from surfactants aka detergents although they may also have other added natural butters or oils. Syndet based bars can be likened to a bottled shampoo in many ways, there is a cross over of some ingredients and they are surfactant based. Lush is probably the best known example of a syndet shampoo bar - therefore soap free.

How do I know what kind of shampoo bar I have?

With a little bit of knowledge this is easy to establish. All shampoo bars will have the ingredients listed, this is a legal requirement and if they haven't then steer well clear as they will most likely not be cosmetically assessed as safe for human use either.

A soap based bar will have a series of ingredients near the top which will loosely resembles the butters and oils they have been made from and they will all be preceded by the word sodium. So as an example you may see something along the lines of sodium olivate, sodium cocoate, sodium castorate, sodium etc.  sheabutterate and so on - depending upon the oils used. Alternatively they may be described as saponified olive oil, coconut oil etc. They will also have glycerin listed , this being a natural by product of the soap making process.

A detergent based or syndet bar will have a completely different list, there are many surfactants (detergents) that can be used but you may see something along the lines of sodium lauryl sulfate , sodium coco sulfate, sodium cocoyl isethionate, cocamidopropyl betaine and the list goes on. You may also find these bars advertise themselves as soap free.

Which shampoo bar is best for me?

The million dollar question and one that I cannot answer, sorry, I know that may not be what you want to hear. 

I can share my experiences however. I have tried soap based shampoo bars. My hair felt awful, straw like , vinegar rinses did nothing for me and I gave up. It is worth mentioning that I have fine , curly mid length hair and a lot of it. We also have hard water. I did a bit of research on it and my understanding is that the hig PH of the soap lifts the cuticles of our hair and leave that rough, straw like feel. The idea of the vinegar rinse is to counteract the high PH and flatten down your cuticles again. The minerals in hard water can also have an impact. I have read of a transition phase, I admit,  I didn't last that long. However, that is just my experience. I know there are many people out there who swear by soap based shampoo, love it and have a full head of happy, healthy shiny hair.

I have also tried detergent based, syndet bars and I find these absolutely fine, I have no problem with them at all however I used a good quality bar which was SLS free. You really do get what you pay for a a cheap shampoo bar will contain cheap (and possibly harsh) ingredients but there are so many out there you need to do a little research and there is an element or trial and error without a doubt. The same goes for soap based bars, the combination of butters and oils that can be used is phenomenal, what works like a dream for your friend may not work for you.

Shampoo bars advice

I would love to be able to recommend a specific shampoo bar to you but I can't. As you can see from all the above there is so much that needs to be taken in to account and not just your hair type. Your water supply may well have an impact too.

Having chatted to some other soap makers there are a couple of top tips that are well worth trying if you would like to try a soap based bar, ultimately this is far more natural than a detergent bar and kinder to the environment so do give it a try.

  • really lather up your hair well
  • rinse, rinse rinse, rinse, rinse and then rinse again!
  • use a vinegar rinse, it can be apple cider vinegar but any vinegar will do the job. Try different dilutions of vinegar to find what works best for you

  • if you cannot get on with soap based just use a syndet bar, try and avoid ones with SLS if you have sensitive skin. The bottom line is you are still saving a plastic bottle and now you have read this blog and understand the difference it will be easier to identify what you are actually using

Do I teach shampoo bar making workshops?

No I don't but there is a good reason for that. For me to teach something I need to love it myself. I could probably make a fortune teaching how to make soap based shampoo bars as they are so popular but it would be very apparent that I am not keen myself, the formulation would probably be far from ideal and that would make me feel uncomfortable about the whole scenario.

Soap makers spend months and years perfecting their shampoo bar recipes so to come up with a good generic recipe just is not possible. Making a syndet/detergent based bar is a whole different ball game, whilst I have a bit of an understanding of them I do not know enough to be able to make a good one myself.

However, all is not lost. Soap based shampoo bars are made using the same method and science as soap and I can absolutely teach you how to make soap. Once you have nailed the basics there would be nothing at all to stop you researching the topic and having a go at making your own shampoo bar to suit your particular circumstances and hair type.

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Comments (2 Responses)

01 June, 2021

The Soap Coach

Ahh thankyou Jan, it is a bit of a minefield tbh hence why I don’t even try and teach it !! Keri

01 June, 2021


Thanks for this blog, Keri. I’ve been wondering about making shampoo bars for a while, but didn’t really know where to start – I didn’t even understand the term ‘syndet’ until I read your blog. I buy Lush bars, which I find work for me although they’re quite expensive. Maybe one day I’ll try to make my own, as it sounds too complicated for me right now!

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