Shampoo Questions

So I have washed my hair twice with Dr. Bronners Teatree barsoap and i must say that i really like it so far. The soap seems to rinse out very well and it doesn't leave a sticky feeling at all. I feel that this change of my washing product has speed up my dreading process at least a bit. I am very happy with the Bronnes barsoap and will continue washing my hair with it, And it is a product which is easyly available in Europe, too! Over here in Germany i could order it over amazon.de or get it at every Douglas perfume store for the same price (5,99 Euro). So i can fairly recommend it for washing dreadlocks!

How often should a person change up their shampoo? I've been washing with the same bar soap for a while now, still seems to work well, but I also have liquid dr bronners (the peppermint variety), and I'm wondering how long a person should use the same shampoo on their hair for before changing to another one....I mean I'm fine with washing with this bar until it is done....but that may last me into next year at this rate, LOL.

why would you ever have to change if its working for you

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My new book Ban The Taboo Vol 1

Well I'm proably going to have to only based off this soap being hard for me to find again, as it was a gift and I'm unsure where to get it, I mean I know the maker so I could order it, but I prefer to go for more readily avaliable products that are good for me my hair. So I plan to use it until it's gone and move on to that lavender soap I had posted about, as I bought a bar recently.

I was recently at the closest Trader Joe's to me, and found two bar soaps and was wondering if they would be ok for my hair. Although I'm still using the beer soap I have and have a bar of Yardley to use, I'm always on the look out. So what do you guys think of these

They have a tea tree vegetable soap contains: Sodium Palmate, Sodium Palm Kernelate, water, Glycerin, tea tree oil, Sodium Chloride, Pentasodium Penetate.

Two different Lemon Verbena-green tea soaps one  lavender and wild rose  called

One called  called verveine-Citron: Sodium palmate, water, Fragrance (Parfum), Glycerin, Elaesi Guineensis (palm), acid, sodium chloride, butyrospermum parki (shea butter), Tetrasodium EDTA, Tetrasodium etidronate, iron oxides, chromium oxide greens, 

The one called the vert seems to have similar ingridents to first one except no iron oxides or chromium oxide greens :

Sodium palmate, water, Fragrance (Parfum), Glycerin, Elaesi Guineensis (palm), acid, sodium chloride, butyrospermum parki (shea butter), Tetrasodium EDTA, Tetrasodium etidronate. 

So would any of these soaps be worth trying? (excuse any typos in the chemical names).

Glycerin leaves residues (if you have some in your toothpaste it leaves them there too), Tetrasodium EDTA and tetrasodium etidronate are made from formaldehyde so that's not good. I wouldn't use them.

If those two ingredients are made from formaldehyde, then how are they actually sold for safe use as soap? ...thanks for the heads up, that saves me from buying them for my hair.

• Because they are made from it. They are a registered carcinogen. Like many other chemicals they are considered "safe" if used in small doses. When you consider how many of these chemicals we are actually surrounded by it's likely many of us are over that "safe" threshold. 

Granted I wash my hair two or three times per week. I alternate between the old baking soda "Shampoo" and the liquid Dreadlocks shampoo made by Buck's County Soap Shop . 

updated by @goldeneagle: 12/08/16 12:14:25AM

I had learned on this site that the baking soda "shampoo" is no longer recommended by Soaring Eagle due to it weakening hair strength.