Well it's kinda hard to tell over the internet, but it might be an idea to check with your doctor. If you're still exercising lots to lose loose skin on your tummy (loose skin won't go away by exercise, I don't think), you might be losing more than you should from the rest of your body. A doctor would be the best person to ask.
35kg lost. (November 2005 - October 2006)
15kg gained again (as at October 2010).
Back to the drawing board - Let's do this thing!
"You can't change the winds, but you can change the sails"
"Reach out and take control of what lands in your lap"