For the most part, hair growth is easy to see -- just look for new hairs in areas of your scalp that have visible thinning. These hairs may start out as small dark spots on your scalp as they begin to grow from the hair follicle and out through your skin.
Your hair grows about one inch every two months, meaning an approximately three inches hair growth in a six-month period and six inches of hair growth over the course of one year. It's important to understand that your hair is made up of two separate structures, each of which plays a role in its growth.
Hair growth is regulated by male hormones (androgens, such as testosterone and dihydrotestosterone), which are present in both men and women but in different amounts.
Growth begins at the root (dermal papilla) in your hair follicle, which gives your hair blood supply and the nutrients it needs to grow. Your hair grows about 1 centimeter per month.
During the telogen phase, the follicle rests for two or three months, and then the hair falls out. The next anagen phase begins as a new hair grows in the same follicle. Most people lose 50 to 100 hairs per day as part of this natural cycle.
Anagen growth is the active phase in which the hair follicle takes on its onion-like shape and works to produce the hair fiber.
The Four Stages of the Hair Growth Cycle: Anagen, Catagen, Telogen & Exogen.
Genetics, hormones, nutrition, and stress levels all play a role when it comes to the health and growth of tresses. An average person loses about 50 to 100 hairs every day and grows the same amount.
Even the frizzies can be part of the natural processes of your scalp's healthy growth cycle. As long as you're practicing good hair care and keeping your scalp and strands hydrated, you're well on your way to new growth!
Each individual hair follicle grows a single hair in a cycle consisting of a long period of growth (about 5 years) followed by a relatively short period of rest (about 3-4 months). After each rest period, the hair is shed, and a new hair begins to grow, and the growth cycle starts again.
Itching is normal when new hair starts to grow in. The itch usually goes away after a few weeks as your hair gets longer. If the itch is severe, you may have an underlying skin condition like psoriasis or seborrheic dermatitis.
According to Web MD, most hair strands grow at an average rate of about 0.3 to 0.4 mm a day. Therefore hair will grow: Around 2.5 mm, or a tenth of an inch, in a week.
The Telogen phase
This phase begins with a resting period, where club hairs rest in the root while new hair begins to grow beneath it. This phase lasts for around 3 months.
The good news is that an itchy scalp isn't likely to cause hair loss, at least not directly. However, some skin conditions that cause you to develop an itchy scalp may affect your hair follicles and contribute to hair shedding and patches of hair loss.
You can distinguish the difference between breakage and new growth because the new growth will be all the same length and all over the head, explains Capri. "If the flyaways are in just one section, it's most likely breakage."
Asian hair is also the fastest growing, at over half an inch per month. Caucasian hair can be stick straight, wavy, or curly. The follicles have a slight oval shape, making it quite dense with an average hair growth of just under half an inch a month.
The anagen phase is the longest, lasting up to 7 years, and is the phase in which the hair actively grows. This is followed by the brief catagen phase, which marks the transition into the telogen phase, which lasts about 100 days, and ends with the hair being shed.
The “awkward stage” occurs when you have decided that you no longer want short hair and you will instead grow it out. Everyone's awkward stage is a bit different depending on their styles, but inevitably, you will find that your hair looks shaggy, uneven, or simply messy at some point in the process.
The First Stage – Anagen
You can tell your body hair is in this phase when it's above the skin and ready for removal. It's still attached to the papilla, which is a nipple-like protrusion at the base of the hair follicle and remains in this part of the cycle for two or three weeks.
This occurs because the growing stage (Anagen) is cut short and hairs enter the falling (Telogen) stage at the same time. The anagen phase constitutes about 90% (1000 days or more) of the growth cycle. The catagen phase (10 days) and telogen phase (100 days) constitute only 10% of the hair growth cycle.
The telogen phase is the shortest and least active stage of the hair growth cycle. This phase lasts for 3-6 months and during this time, hair grows at a rate of 1-2 inches per month.