What is the innermost core of the hair shaft called?

The innermost core of the hair shaft is called the medulla. This central part of the hair structure is typically found in thicker hair types, while in finer hair, it may be absent or not fully developed. The medulla's composition consists of loosely arranged cells, and it plays a role in adding strength and stability to the hair strand.

Understanding the hair structure is essential in natural hair care because different hair types may respond differently to treatments and products based on their specific composition and characteristics. The medulla, while not crucial to the hair's overall appearance, contributes to the integrity of the hair itself, which is important when considering hair health and care routines.