The Science of Hair Growth: All you need to Know about Your Hair Growth Cycle
May 2nd, 2019 by Candis Hall
Hair growth optimization is heavily dependent on understanding its science, as there is much more to hair growth than you can imagine. Have you ever wondered why you need to shave the hair on your head and not the one on your arms, or why some people can effortlessly grow their hair beyond their waist while others can’t? Does losing your hair in the shower worry you? Or is that normal?
Understanding the growth cycle will help you appreciate the entire process, right from the growth phase, to the shedding and regrowing. The tips shared here will go a long way in helping you combat hair loss and demystify everything about hair growth.
What are the Steps Involved in Hair Growth?
First things first, you need to understand that hair is composed of two parts: the shaft and the follicle.
The follicle is the root of hair, from where the shaft grows. Your scalp contains over 100,000 hair follicles whereas the rest of your body has over five million hair follicles. Follicles live in cycles of long growth periods and short rest periods.
The shaft is the part of hair that we can see. It is protected by a layer of protein, referred to as the cuticle. Hair shaft is made up of the keratin (a hard protein). Hair shafts are dead cells, and this explains why there’s no pain felt when we cut our hair!
The 4 Phases of Hair Growth Cycle
The hair growth process involves the following phases:
- The Anagen/growth phase – Hair increases in length
- The Catagen/regression phase – Hair follicles shrink and collapse
- The Telogen/resting phase – New hair begins to grow, replacing the older hair
- The Exogen/shedding phase – Older hair falls out of your scalp
These four stages last for varied lengths of time. Your hair grows for a number of years before getting into the catagen, telogen or exogen phase. To understand these processes better, we have provided detailed information below.
The Anagen/Growth Phase
- Hair is continuously and actively growing.
- Lasts between 4-7 years.
- Hair increases by half an inch on average every month.
- Hair growth rate is high during summer as compared to winter.
- Bulb cells divide rapidly, resulting in high growth rate.
- People with an extended anagen phase tend to have longer hair.
- The anagen phase is affected by nutrition, age, genetics and overall health
- This phase determines the maximum length to which your hair will grow. This is usually between 20 and 30 inches.
The Catagen/regression phase
- Comes right after the anagen phase.
- The hair follicle starts to shrink and detach from the scalp.
- The process of hair falling is initiated, although it doesn’t fall off until much later.
- The follicles begin preparing themselves for the resting phase.
- Deeper sections of hair follicles start collapsing, detaching themselves from blood supply.
- New hair begins pushing out from the scalp.
- Lasts between two to three weeks.
The Telogen/resting phase
- This phase lasts between three to five months.
- It is the stage just before new hair starts pushing out the detached hair.
- About 20% of people’s hair is in this stage at any time.
- This stage can also be triggered by health conditions, stress or when physically unwell.
The Exogen/shedding phase
- Old hair detaches from the scalp and falls off.
- This stage can be noticed when hair sheds during brushing, using a comb or when in the shower.
- New hair grows, replacing the old hair.
- An average of 100 to 150 hairs get into this stage every day.
- The growth of new hair completes the growth cycle, replacing all the hair lost during catagen, telogen and exogen phases.
The Hair Growth Process
This process can be interrupted by external factors, just like any other naturally occurring processes. Such factors include malnutrition, stress and illness.
Stress, for example, can inhibit hair growth by prematurely triggering the catagen phase. Protein deficiency results in a premature trigger of the telogen phase.
The hair shedding process takes several months, hence any changes in diet will be manifested physically after a certain period of time. Stress and lack of minerals could take months before manifesting.
To be on the safe side, always take care of your health by consuming the appropriate amounts of minerals and vitamins if you wish to have healthy, strong, thick hair all year round.
Why should you understand Your Hair Growth Process?
When you understand the hair growth process, you are able to tell the difference between hair loss and regular shedding.
You are also better placed to handle hair conditions such as thinning, because all you need to do is to identify its cause and take necessary actions to rectify this.
Also, you are saved lots of stress because you get to understand that shedding is a natural process, and has to occur for new hair to grow.
For the most part, it is advisable not to panic when you notice your hair’s growth rate is relatively low. Instead, make an informed decision on how to approach your hair’s condition.
Even though growth rates may vary from one person to another, the process is still the same.
Experiencing the best growth rate is up to you. Take good care of your hair, and it will surely thank you, regardless of how long it will take. While at it, it’s important to remember that sometimes the way your hair grows is up to your body. Patience is all it takes to see tangible results.
About the Author
Candice Hall is the Marketing Manager of Dynasty Goddess Hair, with a factory in Thailand & Office and Shipping Center in West Palm Beach, Florida, they are one of the top retailers in Virgin Remy Hair Extensions in the USA.