How does stress negatively impact the hair growth cycle?

High levels of oxidative stress (and emotional stress) can disrupt the normal hair growth cycle by shortening anagen, the active growth phase. This pushes follicles into catagen and telogen sooner than normal, which can lead to earlier shedding.

At the cellular level, oxidative stress can interfere with the function of key follicle cells, particularly those in the dermal papilla, which helps regulate hair growth. It may also increase apoptosis (programmed cell death), further weakening the follicle and affecting the growth cycle.