The hair shaft is the visible part of the hair that extends beyond the skin’s surface. Understanding its structure, composition, and how it is affected by various factors can help beauty professionals and estheticians provide better care for their clients, ensuring healthy hair and addressing hair-related concerns.
The hair shaft is the part of the hair that is visible above the surface of the skin. It is made up of dead, keratinized cells. Keratin is a protein that gives the hair its strength and structure.
The hair shaft is made up of three layers: the cuticle, the cortex, and the medulla.
- The cuticle is the outermost layer of the hair shaft. It is made up of overlapping scales that protect the inner layers of the hair.
- The cortex is the middle layer of the hair shaft. It is made up of protein fibers that give the hair its strength and structure. The color of the hair is determined by the melanin content of the cortex.
- The medulla is the innermost layer of the hair shaft. It is made up of loose, air-filled cells. The medulla is not always present, and it is more common in thick, coarse hair.
The hair shaft is susceptible to a number of conditions, including:
- Damage from heat styling, chemical treatments, and environmental factors can damage the hair shaft, making it weak and brittle.
- Breakage can occur when the hair shaft is damaged.
- Loss of hair can occur due to a number of factors, including alopecia areata, telogen effluvium, and male pattern baldness.