Just as stress can cause a breakout to erupt on your chin, it can encourage hair to revolt. The second biggest offender for people with density loss and lifeless-looking hair is stress. Each piece of hair has its own circulatory system, a sweat gland and a sebaceous gland.  With Stress, each follicle becomes tight and rigid. Essentially stress spikes adrenaline production, which canconvert into androgens (male hormones) including testosterone) and cause extra hair to fall out. Yoga and Meditation can help or you can ask your doctor about prescription anti-androgen treatments.