I agree with Sue and Ruth. This CAN happen, but it is no more likely to happen with a low carb "diet" than with any other diet. I know a girl who can't keep herself from throwing up if she even thinks there was fat in something she ate. And it's not bulemia as she doesn't force it, just the fear that she will get fat again from eating fat. Her skin has lost most of it's elasticity and she is so skinny you can see all her bones. It's horrible, and she's not even 30 yet.
I really think that any program can be taken too far, but I also think that if you look at this as a lifestyle change and concentrate on your health and fitness levels rather than on what the numbers on the scale are saying you should do fine. If you find yourself afraid to eat anything then you should definitely take a look at the reasons behind it as that is unhealthy and we are working on becoming the most healthy beings we can. Remember, we want to be around for years to come, and we can't do that if we are dying of malnutrition, and that means not completely cutting out any food group for long periods of time. Cutting down on, or restricting the timing and ammount is usually fine, but don't completely cut anything out that your body needs. (Of course more power to you if you can completely cut out refined sugar!)
Lara