The hair growth cycle, explained
5 min read
Anagen, catagen, telogen and exogen, why shedding is normal and when it stops being normal.
Four phases, always running at once
Every follicle on your scalp runs its own independent clock. Roughly 85-90% of follicles are in anagen (active growth), which lasts two to seven years and determines how long your hair can get.
Catagen is a short two-week transition where the follicle detaches from its blood supply. Telogen is a three-month rest, and exogen is the release of the old shaft, the hairs you see in the shower.
Why 50-100 hairs a day is normal
Because roughly 10% of around 100,000 follicles are resting at any moment, a daily loss of 50-100 hairs simply reflects normal exogen turnover.
The signal that matters is not the count but the trend: a widening part, a receding density at the temples, or a sudden increase that persists past six weeks.
What a regimen can and cannot change
Topicals and constitutional support work by lengthening anagen and shortening telogen. They cannot revive a follicle that has already scarred over.
This is why early, consistent action outperforms aggressive late action, and why photo tracking every four weeks is worth the small effort.