You see, for the most part shampoos are designed by people with type 1 or 2 hair (typically Caucasians and Asians) for their type of hair. Their key problem is greasy hair, very curly hair's key problem is dry hair - you cannot solve these two problems with the same product!
The main function of shampoo is to clean hair. It is a detergent. The difference between shampoo different shampoos is the strength of the detergent. The key types of shampoo:
1. Regular, commercial shampoo
- Use sulfates as the key ingredient, e.g. ammonium lauryl or laureth sulfates (ALS) / sodium lauryl or laureth sulfates (SLS).
- These chemicals are too harsh for black hair because along with dirt they remove good, natural oils that black hair need to stay soft.
2. Clarifying shampoo
- Stronger than regular, commercial shampoos
- Designed to remove heavy product build up from thick greases, gels and pomades
- Even if you use very heavy products on your hair, you shouldn't be using clarifying shampoos more than once a month according to The Science of Black Hair
3. Chelating shampoos
- Stronger than regular, commercial shampoos AND clarifying shampoos
- Designed to remove mineral deposits that are sitting on hair
- Whilst clarifying shampoos just remove dirt from the surface of hair, chelating shampoo affect the hair's bond structure.
- If at all, this very strong shampoos should only be used every 4 to 6 weeks by those living in a hard water area
The better shampoos for black hair
- Cocomidopropyl betaine is a gentler cleanser and more suitable for black hair.
- Sulfate-free shampoos. That said, not all sulfate-free shampoos are equally good for black hair but that's a topic for another blog!
Ref: Science of Black Hair, pages 69-72