How hair grows
Did you know that a full, healthy head of hair consists of about 100,000 - 150,000 individual hairs? It’s true. And in a normal healthy scalp only 90% of those hair follicles are usually in a stage of growth at any one time. The remainder are either resting or transitioning.
Identifying an active follicle
Did you know that you have all your hair follicles in place when you’re born? It’s true — and the number never changes. We don’t ever grow or produce more follicles – the ones we have when we’re born are the ones we have for the rest of our lives – no more, no less.
We have follicles all over our bodies, but many of them aren’t active. When we refer to an active follicle, we mean a follicle on your head that’s still able to produce hair.
Hair growth phase 1: Growing
Every hair on your head is constantly going through one of the three stages of the hair growth cycle. The first phase is a growth phase, called anagen, and it can last anywhere from 2 to 6 years. While in this phase, group of cells at the base of the hair, called the dermal papilla, multiply rapidly. As new cells form, the old ones move upward creating the hair you see.
Hair growth phase 2: Transitioning
When the cells at the base of your hair stop multiplying, the hair stops growing and enters the catagen, or the transition phase. This part of the hair growth cycle only lasts for around two or three weeks, before it goes into phase three.
Hair growth phase 3: Resting
Finally, the hair enters a phase called telogen. At this time, the hair rests for 2 or 3 months before it is shed by the follicle. At any time, around 10% of your hair is in the resting phase, preparing to shed – these are the hairs that you notice in your hairbrush, on your pillow, on your clothes or in the shower drain. These shed hairs are a totally normal part of the hair cycle, and it’s said we lose between 50 and 100 hairs every single day, many of them going unnoticed. But don’t fret – as soon as the hair is shed, the cycle starts again.
And we're growing again.
After the hair has been shed, a new hair begins to grow, and the cycle repeats itself — through anagen, catagen and telogen — for each hair follicle on your head for as long as it is active.