I have lost more than an inch from my waist. (Sorry, 2.5 centimeters just doesn't sound right.) I lost around 6, maybe 7, pounds, which is not that much really. Losing inches is a better gauge of improvement.
The main reason is regular, albeit fairly moderate exercise. I'm not dieting but I am eating less due to being on a budget. The snacks were the first to go. I miss my snacks. ;_;
Still, I'm way too stressed to really feel the benefits of this. In fact, the exercise may be the only thing that is preventing me from becoming a total basket case.