Long-term, or chronic, stress puts people at risk for a variety of health problems. These can include depression and anxiety, as well as problems with digestion and sleep. Chronic stress has also long been linked to hair loss, but the reasons weren’t well understood.
Hair growth involves three stages. In growth (anagen), strands of hair push through the skin. In degeneration (catagen), hair ceases to grow, and the follicle at the base of the strand shrinks. In rest (telogen), hair falls out and the process can begin again. Hair is among the few tissues that mammals can regenerate throughout their lifetime.
The hair growth cycle is driven by stem cells that reside in the hair follicle. During growth, stem cells divide to become new cells that regenerate hair. In the resting period, the stem cells are inactive. Until now, researchers hadn’t determined exactly how chronic stress impaired hair follicle stem cells.https://www.nih.gov/news-events/nih-research-matters/how-stress-causes-hair-loss