Hi Ladywear - I have a hairloss issue too and have been trying to figure it out for some time. In mid June I had testing done for thyroid and hormones. I found out that my Progesterone levels were very low--like practically menopaulsal, yet I am just about to turn 41. My thyroid, while maybe could be better, was in the normal range (just slightly under 3), although my dr. said that it is possible to be "thyroid resistant," just like a diabetic can be resistant to insulin, a person can be resistant to their own thyroid hormones--although I think though that this is very rare. It's all definitely a process of elimination, but I think the hairloss in my case is DHT, because DHT "squelches" off the hair folicle's blood supply/oxygen bit by bit until eventually the hair grows no more. I've noticed that some of the hair that has been falling out is very very thin--almost cat hair like--hence the squelching action of DHT. I have been taking natural progesterone caps now for over a month and I am hoping that this turns around--I can say it does seem like I am losing less hair, but that's not all I'm doing about it either--I am using a copper peptide solution on my scalp daily after I wash my hair to break down the built up DHT in my scalp so my hair folicules can receive blood flow/oxygen. I do not underestimate hormones and what they can do to you - they are a big reason for hairloss for both men and women. My mother, who always had lots and lots of hair, since menopause has lost significant hair. You see all the old ladies, guess what? They have NO progesterone, but plenty of estrogen, which converts easily to DHT - see Dr. Wong's article--the Real Reason Men Lose their Hair:
My sister, post pregnancy has been losing tons of hair - it's a hormone change. During her second and third trimester, when Progesterone is really high, she received additional weekly shots of Progesterone (helps keep the baby in the womb). Now, post pregnancy, she has way way lower P (no pregnancy, no shots) and she is shedding hair like mad.
Conversely, I have heard that some who have hair loss will use Nioxin - which kills yeast - and it makes their hair grow back. True? I have no idea.
Also, if a person has gluten intolerance, they can lose their hair from that too, due to a gut that poorly absorbs nutrition from food (if the person is still consuming gluten so their gut lining has not had a chance to heal.)
And yes, there's Iron deficiency - that can cause hairloss too. So, in my book, the big reasons are Gluten Intolerance, Thyroid, lack of Progesterone=high estrogen/Low iron--and not necessarily in that order. If it appears that your individual hairs are getting thinner, I would bet on DHT as the root (no pun intended) problem.