Dry, brittle hair that breaks or falls out can be a sign of hypothyroidism. Too little thyroid hormone disrupts your hair growth cycle and puts too many follicles into "resting" mode, resulting in hair loss—sometimes all over your body including at the outside of your eyebrows. “Lots of my patients come in and tell me that their hairdresser sent them,” says Dr. Miller. “They’ll say, ‘My hair stylist said I’m losing my hair and I needed to go ask my doctor about my thyroid.’ The hair salons are more aware of thyroid problems than some doctors!”
An overactive thyroid can also do a number on your hair. Hair issues due to hyperthyroidism typically show up as thinning hair just on your head.
So, how does one ensure that testosterone levels remain in balance? Some doctors suggest that monitoring testosterone levels every five years, starting at age 35, is a reasonable strategy to follow. If the testosterone level falls too low or if the individual has the signs and symptoms of low testosterone levels described above, testosterone therapy can be considered. However, once testosterone therapy is initiated, testosterone levels should be closely monitored to make sure that the testosterone level does not become too high, as this may cause stress on the individual, and high testosterone levels may result in some of the negative problems (described previously) seen.