Black women hair loss issues is usually due to the lack of knowledge in the products used on their hair.
The relaxer for instance are meant to be proffesional products meant to be used to chemically straighten their hair, but you find most are used in the home as home kits are sold in shops, hence inappropriate use may damage hair causing it to thin and break. Also as black hair texture is a lot less tougher than europen hair, it may not be able to witstand tough colouring process and tends to break as their scalp is a lot drier. The right knowledge on products and after care matters if black hair is chemically changed.