Firstly, I told you I'm not good at keeping journals etc. I'm not sure where all that time has gone, but I did warn you. đ
Anyway, I'm about to get on my soapbox (pun intended) about Shampoo Bars. I'm gonna jump to the main issue, and then rant away.
Most of the so-called shampoo bars you find for sale are NOT shampoo.
THEY'RE F***KING SOAP.
If you see someone trying to sell "Shampoo Bars" Check the ingredients. If you see "sodium hydroxide", "lye", or the word "saponified" anywhere, IT'S SOAP. Don't fall for it! and please don't use it on your hair. A very small percentage of people can use soap on their hair without issue. Most of us really should be using something that is pH balanced on our scalp.
Your hair & scalp are going to have a pH in the range of ~ 3 - 5.5. This means our hair and scalp are acidic... Soap is alkaline. Soaps have a pH usually in the range of 8-10. Not really gelling with your hair (no pun intended, but you know what? I'm leaving it.).
So basically you want something made with surfactants (don't worry there are natural surfactants and safe synthetic ones, don't be intimidated by strange words) and NOT LYE in your shampoo. The shampoo bars that are not soap are often referred to as "syndet bars."
Not all shampoo bars are created equal, and you may have to try different ones before finding one you like (like with other shampoos, and of course it does help to know your hair and what it likes).
Side note: Shampoos can be used as body wash / soap, but soap and body wash should generally not be used in your hair (unless you're desperate).
So yeah, shampoo and soap are not the same thing and a lot of people don't seem to realize it. It's frustrating to me, particularly because when I was trying to research how to make shampoo bars, it took 10x longer to figure it out because everywhere you look up "shampoo bar" brings you to folks selling soap. They should know better, but I can't change that, so here I am ranting on my soapbox.
Don't be fooled guys; if you want your hair to be happy and healthy, learn about your own mop and give it what it needs. Odds are, it's not soap. đ§ź
Thank you for coming to my ted talk. (on a soapbox đ)