Hair and Hair Loss Treatment: Hair Anatomy and Physiology
Before we begin to discuss how we can help you to replace hair that is lost, lets deep dive into finding a little more about hair anatomy and physiology. As mentioned briefly in our first article hair is made of a hard protein called keratin. Even though the part of your hair that you see is dead, your hair is actually a surprisingly sophisticated piece of body equipment. Think about it for a minute.
You’re usually born with some hair. That first hair falls out, and new hair grows in, often a different color than the first hair. As you age, your hair may change color: first getting darker in your youth, then getting lighter in your adulthood. Throughout your life it grows, rests, and falls out at regular intervals mostly determined by genetics.The texture of your hair and the spacing of your follicles is also predetermined by genetics.
And as most women can attest to, it’s frustratingly difficult to get rid of if it’s growing in a place you don’t like. There are two main parts to your hair. There is the hair shaft, the nonliving part you see and the follicle, the living part that resides under the skin. Many of you will have heard of the phases of hair growth: anagen (growth), catagen (transition), telogen (resting), and exogen (shedding.) At any one time, roughly 85 to 90 percent of your hair is in the anagen phase.
Underneath the skin, the follicle is attached to nerves and nourished by blood vessels. Imagine each individual follicle is connected to tiny veins and arteries in capillary form. During the catagen phase, hair detaches itself from blood vessels before the hair falls out. To coax your hair to regrow, we treat the follicles, which are the essential growth parts. In future articles, we will talk about the importance of these vascular structures in treating hair loss.
The hair shaft has three layers, the cuticle, the cortex, and the medulla. The cuticle protects the hair; the cortex is the thickest part of the hair shaft and holds the color pigment, and the medulla determines the hair’s thickness and texture. Some hair types don’t have a medulla.
One of the most interesting things about hair is that it is one of only a handful of body parts that has Immune Privilege or IP. That means hair follicles do not react with a typical inflammatory response in the presence of antigens.
There is still a lot we don’t know about hair, but fortunately, we know enough to treat hair loss in a meaningful way.
This concludes Part 2. In Part 3, we will discuss hair color.