Redhead, isn't being able to eat everything that isn't labelled "poison" and look like a spike at least one of the attractions of running? Fast weight loss scares the h*ll out of me. At the moment I'm happy to lose a bit of weight and would like to shed another half-stone, but not so quickly that tissues other than fat start to melt away.
It got really scary at the turn of the year when I was doing 30+ miles a week, packing away over 3,500 calories a day (try doing that while restricting yourself to a healthy, low-fat, complex-carb diet!) when the various formulas for calculating expenditure suggested I needed about 2,500-2800 calories a day, and disappearing rapidly. I've read since then that heavy exercise can make our bodies produce a substance which causes dramatic tissue loss. I'm obviously one of those who makes lots of it!
Came as a bit of a shock because my normal condition is slightly cushiony. I'm hoping to take the remaining weight off at a leisurely pace between now and the end of the year, but we'll see what happens.
Cheers, V-rap.