The follicle is a tunnel from the epidermis (outer layer of skin) that ends with a pocket deep inside the dermis (2).
Hair cells begin their life and die in this pocket, so the part you see sticking out of your head doesn’t hurt when it’s cut.
You have about 100,000 follicles in your scalp.
The baby bulb (root) of the hair is made of protein cells at the base of the follicle that build a shaft.
Nearby capillaries nourish the bulb as cells divide (3).
Adequate circulation is needed to provide plenty of blood and nutrients to the growing cells.
Massaging your scalp promotes circulation and stimulates hair growth (4).
The blood delivers hormones that signal hair growth and structure throughout life.
Hair bulb cells divide every 23 to 72 hours, much faster than any other cell in the body (5).
Inner and outer sheaths surround the follicles to protect and form a growing hair strand.
The shape of your hair follicle determines whether your hair is straight, wavy, or curly (6).
The inner sheath ends below the opening of a sebaceous (oil) gland, and the outer sheath continues all the way to the gland.
Scent and sweat glands are also nearby (7).
Small, fan-shaped muscles called arrector (or erector) pili or pilomotor muscles attach below the base of each hair that contracts when the body surface is chilled (8).
Contraction makes the hair stand up, causing “goosebumps” to appear, and the sebaceous glands secrete oil, or sebum, to condition the hair and skin (9).
Specific cells in the hair bulb, called melanocytes, make the pigment called melanin, determined by your genes (10).
Two types of melanin, eumelanin and pheomelanin, and their amounts create the color of each strand.