We all know that taking care of our hair is important. Whether we are dealing with specific issues such as hair loss or we are just looking to develop a daily hair care routine, having a basic understanding of how hair grows and functions is key to finding effective solutions.
Let’s get to the root of it.
The hair follicle is the start of growth for your hair. It’s like a little pocket that lives within the epidermis — the outermost layer of skin. There are over five million hair follicles on the average human body with about 100,000 of them being located on the scalp.
Here, the root of the hair is made up of protein cells. Nearby blood vessels help increase circulation and promote healthy hair growth. As more of these protein cells are produced, the hair is pushed towards the surface and develops into the hair shaft — the part you can see and touch outside of the skin.
At this point, your luscious lock is actually just dead cells. New hair underneath the skin continues to grow and pushes the dead hair out of the skin. This base of your hair is not only responsible for hair growth, but also what type of hair you have. The shape of the follicles determines whether you have those tight curls or beachy waves — for example, circular follicles produce straight hair and oval follicles produce curly hair.
Alright, let’s get to the growth part of things. Hair growth occurs in cycles that break down into three specific phases:
- Anagen (growth phase) In order for your hair to be growing, it has to be in this phase which can last anywhere between 2 to 7 years. Typically, the hair will grow about 6 inches a year and 18–30 inches throughout the entire anagen phase. The length that your hair can grow is determined by a variety of factors including age, genetics, pregnancy, nutrition and overall health.
- Catagen (shrinking phase) Hair stops growing and is in the process of detaching itself from the blood supply. This is the shortest phase, lasting 2–3 weeks.
- Telogen (resting phase) The final phase of hair growth is when the hair follicle is completely at rest. It is fully detached from the root and results in hairs falling out or shedding.
Okay, so given this breakdown — shouldn’t there be a period where all my hair is falling out?
No. Humans experience staggered hair growth, therefore at any given time, the average scalp has 90–95% of its hair follicles in the anagen (growing) phase. So the 50–100 hairs that most people shed each day are due to the 5–10% of hair follicles in the telogen (resting) phase. This is all part of the totally normal, healthy hair growth cycle. Don’t worry!
So when it comes to hair care, remember that there are many different factors that affect the hair growth cycle. Hormones, age, sex, and nutrition all play a role in determining how long your anagen (growing) phase lasts for, not just the type of shampoo and conditioner you use. While most hair products on the market can help minimize the risk of hair breakage, they don’t have an impact on the length of your growth phase.
Understanding the anatomy of hair and how it grows will help you maintain the healthiest version of your hair as well as avoid marketing traps for products that make claims that aren’t scientifically proven.