I can see how that *might* be beneficial for someone with low porosity like yourself, t might be a good thing to prevent build up and open the cuticle slightly to allow ingredients to enter. Is there any research backing up any benefits for the rest of us? 'Curl Chemist' Tonya McKay does not advocate them.
"Another very important ingredient to avoid for long, curly hair especially is soaps. In the past, I have written an article cautioning users of soap to be careful, but basically concluding that it was probably okay to use soaps with an acidic rinse and lots of moisturizing agents. Based on the following information obtained from the research of Dr. Ali Syed (a hair care researcher who specializes in African and curly hair), I cannot in good conscience advocate use of any soap products on curly hair.
Soap molecules are salts of fatty acids found in plants and animal fats. They are somewhat alkaline and cause the hair to swell and the cuticle to raise up away from the surface of the hair shaft. These molecules are then able to penetrate through the cuticle and into the CMC where they neutralize the fatty acids in the lipid layer, rendering them water soluble. The fatty acids are then rinsed away in the shower and are gone forever. Use of soap to cleanse one’s hair, especially long curly hair, seems to be a really effective way of permanently destroying the cuticle layer and making the hair very highly porous. This is an example of why natural may not always be superior. It is no surprise that researchers have invested years and many millions (billions) of dollars to develop more gentle cleansers for our hair.
Porosity and Curly Hair
Plus you cannot repair a destroyed acid mantle on the scalp with a dilute vinegar rinse.
2a-2c, medium texture, porous/ colour treated. Three years CG, growing out mechanical and chemical damage = breakage and very high porosity. Past armpit length heading for waist.
CO-wash: Inecto coconut
Treatments: Komaza Matani, coconut oil, Hairveda Sitrinillah
Leave in: Fructis Sleek & Shine (old), Gliss ultimate volume, Inecto argan
Styler: Umberto Giannini jelly, Boots Essentials gel
Experimenting with: going back to basics