Hair Growth and Hair Loss
Generally your hair grows about 6 inches per year. Usually the majority of your hairs (90%) are in a growth phase. There are 3 cycles to hair growth: anagen, catagen, and telogen.
An overwhelming majority of the time the hair is on the scalp, it is growing. Only about 10% of the strands are in transition or resting at any one time. Hair grows about 6 inches a year for most people.Anagen (Growth Phase)
About 90% of your hair is in the anagen or growth phase. This normally lasts about 2-8 years.
Catagen (Transition Phase) Catagen is the transition phase and typically lasts 2-3 weeks, during which the hair follicle shrinks.
Telogen (Rest Phase) The rest phase is the telogen cycle and usually lasts around two to four months.
Many things can interfere with the hair cycle: medication, illness, infection, stress, or chemicals. Even your own body's hormones have the potential to stop hair from being formed properly.