How Hair Growth Works

When experiencing thinning, shedding or hair loss issues, we sometimes become frustrated with our hair’s lack of growth. However, it is essential to understand the hair’s process before working towards regrowth. Educating yourself on how your hair works will not only assist you in choosing the proper products but motivate you to be consistent in your hair care regimen.
Formation of Hair
The formation of hair begins in the hair follicles which are located on the scalp. There are one hundred thousand hair follicles on the scalp alone at the time of birth. As we grow older, we do not regenerate new follicles so this number decreases over time.
Follicles can be seen on the scalp, but they extend below the dermis (lower layer) of the skin like small tubes. The bottom of the follicle meets the blood vessels in the head to promote the health of the follicles. Inside the hair follicle, there are the inner and outer sheaths which work to guide and protect the hair growth shaft that flows between them. At the top of the outer sheath you’ll find the sebaceous oil gland and attached to this gland is the erector pili muscle. The contraction of this muscle causes the hair to stand up and also produces oil. The oil that is released is called sebum, which is necessary for conditioning the hair and scalp. Men are shown to produce more sebum than women. Although sebum is vital to hair growth, excess sebum can lead to oily hair and clogged pores in the scalp. The hair shaft that protects the hair strands is created with a protein called keratin, which is a key element of hair growth and health.
Hair Growth Cycle
Hairs grow in cycles but when each phase of the cycle occurs is unknown. Therefore, the hair growth cycle can be very unpredictable. Hair on the head grows an average of .3 to .4mm a day, which equals about 6 inches a year. The 3 cycles your hair experiences are: anagen, catagen, and telogen. Each of these phases has a specific purpose in helping to maintain healthy hair growth.
Anagen
The anagen phase is when your hair is the most active. New hairs begin to grow caused by cells at the roots dividing at a rapid pace. When these new hairs form, they push out club hair (older hairs that formed and became dormant). The anagen phase ranges in time length. Those with longer hair experience a prolonged anagen phase. Hairs located on areas such as the arms and eyebrows have a shorter anagen phase causing these hairs to be shorter. Even though this phase is the most active of the three, only 80% of follicles participate in hair growth at once.
Catagen
The end of the active growing phase is signaled through the catagen transitional phase. This phase usually last 2- 3 weeks and only includes 3% of the hair at a time. Hair growths stops as the hair outer sheath shrinks and connects to the hair’s root.  This causes the root of the hair to lose its blood supply further delaying its growth. These hairs then become club hairs.
Telogen
This is the official resting stage that impact 6% to 8% of hairs on the scalp. Once the club hairs are fully formed, the Telogen phase begins for around 100 days. At this stage the hairs on your scalp are completely dormant. If you were to pull a strand of hair out during this stage, it would reveal a hard, white formation at the root. On average 25 to 100 hairs will shed daily during this phase.
How does this effect hair growth regimens?
Everyone’s hair goes through these repeated cycles. When dealing with hair loss, it is important to realize your hair grows in phases. You should maintain your hair loss regimen, such as hair loss shampoos, supplements and minoxidil, throughout these phases for the best results. Even though your hair may be in the telogen resting phase, the beneficial products for hair loss are still repairing your hair and promoting growth. Ingredients through all stages of the hair cycle, but your hair will still experience dormant periods of time. Due to this resting phase, hair growth results for hair loss products are usually visible within 6 months to a year. The best practices during your quest for hair growth are consistency and patience and knowing the cycle of hair growth will help you with those practices.