Actually, significant weight loss by *any* method often results in hair loss, as do hormonal changes (pregnancy, menopause, etc). This article from LowCarbLuxury.com has an explanation of why:
http://www.lowcarbluxury.com/newsle...3-no06-pg7.html
I sympathize with you, WannaLose, because I also have very long blonde hair, and it's always been my one vanity. I did go through a period of hair loss a couple months after starting Atkins, and I blame it completely on losing about thirty pounds in three months. I hadn't been fad-dieting, took my vitamins, and was eating very healthy LC (lots of veggies, very little frankenfood, fresh and high-quality everything), so I just don't think external factors played a part in it. I just lost a lot of weight very quickly, and that puts a stress on your body regardless of how you lose it. I never got anywhere approaching bald, though, and the only ones who noticed it were me and DH (who mainly noticed the unbelievable shedding rate). It was actually kind of a good thing, because I had a *lot* of hair, enough to break barrettes and destroy the elastic in scrunchies. It's a little more manageable now that there's not quite so much of it! However, it's starting to really grow again, so I have massive attacks of the "wispies" because of all the short hair around my face.
The hair loss thing freaked me out, but it wasn't worth quitting and going back to high-carb. I felt so amazingly better, and the weight was just falling off; much as I loved my hair, it wasn't worth continuing to look and feel like crap. It's only hair, and it does grow back in time. It'll be back where it was in a couple years, and then I'll have it all -- I'll be thin, energetic, healthy, AND a shampoo commercial waiting to happen! I think my health and overall happiness are a higher priority than my hair, but I guess you'll have to make that decision for yourself. It may happen, it may not, and you'll have to risk it if you stay LC. Obviously, you're unhappy enough with the way things are to start LC in the first place, but only you can ask yourself if you're unhappy enough for it to be worth a little hair.