Soap & Shampoo

Pig Cat · Sep 15, 2008

Hi there,

Can somebody please tell me the basic difference between soap and shampoo please? What is to stop me using soap on my hair? I haven't tried this yet, but wondered about using good quality bath soap as a shampoo. Is this completely nuts, or can it be done?

Norbert Sykes · Sep 15, 2008

Here's a good article titled "What is the difference between soap and shampoo?" from chemistryquestion.com.
http://www.chemistryquestion.com/English/Questions/ChemistryInDailyLife/1c_Shampoo_Soap.html

The answer can be summed up in the first sentence:

The main reason for development of shampoo was that hair became rough and damaged when soap was used to wash hair

Other notable quotes:

Alkali gradually causes damage to the proteins of hair. It may also react with other preparations for hair and cause problems. In addition, soap reacts with metal ions (Ca2+ etc. ) and forms a complex called scum, which is also not good for washing hair. (You are able to see scum on your bath tub.)

In many current shampoos, the higher alcohol typeanion surfactant provides the proper detergency and forms rich bubbles, and a non-ion surfactant is added as coadjuvant. The reason why more than one kind of surfactant is employed in shampoo is to make better bubbling and to have a more beautiful finish for the hair.

In addition to surfactants, many other ingredients are added to shampoo in order to prevent dandruff, to treat the hair, to rinse the hair and to give him/her a fresh feeling, etc. This is the difference between shampoo and soap.

What if shampoo is used for washing a body?
As has already been mentioned, shampoo has many functions besides taking out dirt. Thus, these functions would not damage skin, but there would be some disadvantages for example, many ingredients in shampoo are not needed for skin (bad efficiency), and you might feel a bit slimy. In addition, the cost of shampoo is usually more than the cost of soap.

Pig Cat · Sep 16, 2008

Many thanks, Norbert. In that case I think I'll stick to shampoo! :001_smile

Eagle · Sep 17, 2008

I have attempted the hair wash w/ bar soap in an emergency. Leaves the hair dull and the scalp itchy. I don't recommend it unless you've no other choice.

sol92258 · Sep 17, 2008

I'd recommend against "sham"poo and demand "real"poo.....

but seriously, that is good information to know, I never really thought about it until someone mentioned shampoo bars awhile back; still can't see how you'd use it though

Norbert Sykes · Sep 17, 2008

sol92258 said:
I never really thought about it until someone mentioned shampoo bars awhile back; still can't see how you'd use it though

From this site that sells shampoo bars:

This is what I do. Your methods may vary, depending on the length and type of your hair, the hardness of your water and so on. But still this may serve as a starting point for you.

I get in the shower, wet down my hair thoroughly and grab a shampoo bar. I use it directly on my hair, applying it in a combing motion from the front hairline down to the nape. I do this combing motion maybe a dozen times, then I start to lather up with my hands, massaging well and adding more water as needed. Again I take the shampoo bar and slide it down my length all the way down to my ends, again maybe a dozen times. I massage and gently squeeze the length (more of a straight motion, rather than a circular one this time). I rinse. I repeat. Yes, I lather a second time. And I lather a third time, but only my canopy, while I use a soap bar (soap bars generally are more moisturizing than shampoo bars) on my length and ends as a conditioner. I let this sit for a minute or two while I perform my other showerly duties. I rinse well.

If all shampoo bars are similar to the ones sold from the site above, using them doesn't sound like a very good idea.

Since alkali damages hair and helps scum to form, this isn't exactly good news:

All soaps (and shampoo bars) have a pH-value of about 8-10 and therefore are alkaline.

So why use one? These reasons are given:

For me the main pro is that a bar shampoo can be made with fewer and more natural ingredients than liquid shampoo. For instance, a solid shampoo doesn't need to contain preservatives. It's also practical, a shampoo bar can double as hand, face, and body soap, you can do your laundry with it and maybe even the dishes. Alright, that's carrying it a bit far, but if you are a hiker and camper like me you'll see the advantage

Who cares if there are fewer ingredients? What's the importance of "natural"? Unless there are good reasons that the ingredients in shampoo are harming us, this reason is irrelevant. Practical and a hiker and camper can see the advantage? Well, it seems the person writing the above admits to the problem with using an alkali for hair and offers this solution:

There are different opinions on the nature of the acidic rinse as a round-off to the shampoo bar. The acidic rinse serves as a neutralizing agent to the alkaline soap, making it easier for your skin to regain its natural acid mantle. It also smoothes the hair shaft, thus making your hair shinier. And it helps to remove any soap residue and mineral deposits from hard water. Some people never use an acidic rinse; some use it only sometimes. Some swear by apple cider vinegar (ACV) or citric acid.

I use plain white vinegar after every wash, in a dilution of 1 in 10 (100ml vinegar and 900ml water). The harder your water is the stronger your rinse will have to be. It may take you a while to find a dilution that works for you, so don't be afraid to play around. Some people claim vinegar rinses to be drying for the hair. I have never experienced this, but you might want to keep it in mind if you have dry hair anyway. Oh, and by the way: The vinegar smell disappears as your hair dries, so you won't walk around smelling like salad dressing!

OK, so I take a jug with 100ml white vinegar into the shower with me and fill it up from the tap. First I dunk my length in it and swish it around some; then I slowly pour the rinse over my head, making sure every area gets a fair share. I let it sit for a minute and kind of pat it through my hair, then I do a fairly quick final rinse, and I'm done.

That doesn't sound very practical to me. It sounds more like a lot of trouble someone would go through to wash their hair with soap and not one good reason has been mentioned for doing so. I'm betting it's, "Hey, I'm making money making soap, maybe I can make a tweak or two and claim it's shampoo in a bar and make even more".

Gotta love the Troubleshooting section:

My hair feels coated, waxy and generally weird. This is an indication of buildup. Did you use a soap bar on your hair? This may be the culprit. Or try to increase the strength of your vinegar rinse.

Oh, your hair feels "coated, waxy and generally weird"? You must have used a shampoo bar. That'll do it to you. Ready to place your next order?

I shed a ton when washing with a shampoo bar. That was what I experienced at first, and it really scared me. I believe you often shed more when you first start on a new routine; also remember that with shampoo bars you need to massage a lot, and the hairs you shed that way were bound to go anyway. In my experience I do shed slightly more during my showers, but significantly less in between.

Yes, shedding a ton is normal. It's okay, it's only because it's a new routine. You won't notice this so much when you have less hairs on your head.

koso · Sep 17, 2008

Norbert Sykes said:
Yes, shedding a ton is normal. It's okay, it's only because it's a new routine. You won't notice this so much when you have less hairs on your head.