I've been riding partially to lose weight, partially to have a healthier body, and partially for fun. But no amount of riding helped me lose anything until I changed my diet. It's just a simple fact of life, I guess. Now I'm down 30 lbs and still working on it, but I don't credit the riding so much for weight loss as I credit it for making me feel better by getting regular exercise. Seems like I sleep better and have more energy. Of course running/jogging or other forms of exercise will do that too, it's just that biking is my preferred mode.