Does anyone know why an underactive thyroid causes dry, thin, and brittle hair? I had my Thyroid tested a couple of months ago and my TSH was around 5.0. Thinking back, I remember my hair turning dry, thin and brittle in 3rd or 4th grade. I now assume I had an underactive thyroid way back then. I am now 39
It's a mistake to assume that every symptom that can be associated with hypoT is caused by hypoT. If you had no other signs of it then, like smaller than average stature, learning disabilities, lethargy, impaired immunity, constipation, etc... then you probably were not hypothyroid at that time and your dry hair was caused by something else.
HypoT can slow down almost every body system. Not every hypoT person experiences all of the possible symptoms, though. Oil glands can produce sluggishly, hence dry hair and skin. Hair falls out excessively because the hair growth cycle is interrupted, making the older hairs fall out sooner while the new ones are slower to replace them.
Interesting to note... There is credible evidence that having only one gray hair before the age of 30 means that person is predisposed to low thyroid later in life. My best friend found a gray hair among my auburn ones when we were only in 4th grade.
because your body is burning the calories you consume so quickly, your body needs more fuel ( obviously ). If it does not obtain this, it reaches "starvation mode" in which it only gives energy to the places which absoulutly need it, due to the lack of fuel. Obviously, places like hair is not a place which the body considers absoulutly nessesary for survival. Are your fingernails brittle too? This normally accompanies the dry and brittle hair.