At one point I was down around 5 lbs, which is 5% of my current bodyweight, and in the underweight range. I was very much struggling with change and found myself unable to go shopping for a couple of months, which certainly wasn't healthy. It was a bit of a wake up call to be honest, to realise how far I'd go to avoid being in a situation where I didn't know what to expect.
I'm currently back to exactly where I was 6 months ago, which is just the right side of healthy and where I normally sit. I feel heavier though as I've not been able to do my normal form of exercise (climbing) and it's too hot to me to get out as much as I'd like. Unfortunately, wandering around here in the middle of the night isn't the safest idea. I should probably watch what I'm eating a little more now that I'm back at my proper weight though, I'll admit that I've been paying less attention while trying to build myself back up. It's also been tempting to buy "nice" stuff now that I'm shopping again after meals of tinned fruit and beans.