I lost a LOT when I came off TFR. It seems that while on TFR your new hair stops growing, then when you start eating again new hair starts to grow and pushes the old hair out. So its really the old hair falling out while the new hair grows. For me it lasted a couple of months, although I have a good head of hair it was not noticeable and it does stop. If you have thin hair I would imagine its very noticeable given the amount you can lose. Hope this helps xx