Normal Hair Growth Cycle

Hair Growth Cycle

The average human head has around 90,000 –120,000 hair follicles, growing at an average of 0.5 to 1 centimetre per month. Each hair follicle follows a cycle of growth until it sheds at the end of the cycle. There are 3 main phases in the hair growth cycle: 
1. ANAGEN (GROWING) PHASE
-    Growth phase of the hair follicle and new hair is formed.
-    Approximately 85-90% of the hair follicles spend 2 – 5 years in this phase.
-    This is the only phase where laser therapy is effective.

2. CATAGEN (TRANSITION) PHASE
-    Intermediate phase of hair growth.
-    Lasts for 1 – 2 weeks.
-    The dermal papillae - a group of cells that contain blood vessels and nutrients supplying the hair follicle, begins to separate from the hair follicle. 
-    Hair follicles slowly transition into the resting phase.

3. TELOGEN (RESTING) PHASE
-    The dermal papilla is completely separated from the hair follicle.
-    Old hairs reach the end of their cycle and falls out.
-    Lasts for 3-4 months.
-    At the end of this phase, new hair growth is initiated.