I have been sugar-free for 10 months now and had found the solution to years of trying to diet.  I was so happy and was able to eat normal amounts of any other food.  2 months ago I suffered chronic sciatica with pain down both legs and have found going for any sort of walk impossible.  Because I have continued to want to eat the same amount as I did before I have started to put some weight back on.  The weight gain certainly isn't as much as it would have been if I was still eating food with sugar in but I still find it very frustrating.  It proves that a moderate amount of exercising such as a 20 minute walk each day is essential in maintaining the weight loss.