Another post from dcmichael74 is on the board and I just posted on that post about this same thing.
Take a look at that post and read the information along with Red's comments here and see if that helps you understand more.
Have you been diagnosed with a thyroid disease? Hair loss can be attributed to many things, but being a thyroid patient and usually (not always so though) Hypothyroid patients notice hair loss big time. (me included!)
You would be best to get full thyroid function tests done. TSH, Free T3, Free T4 and antibodies. Post them here with the reference ranges written on the lab result and we can help you further.