It's so much easier to get the weight off when you're young, no matter what it comes from. Once ya hit 35, your metabolism slows down, and it keeps slowing down. Depending on your job, you won't get enough exercise anyway. You're so damned tired from work, who the hell has any energy to exercise? If you're female, and have kids, there it goes. And then, to make it even more joyful, getting older opens the door to more metabolic disorders. Thyroid shuts down, Diabetes, stress and overwork, bah. Being an adult has it's advantages, but wow, getting older sure sneaks up on you. And if you're in some sort of accident where you can't move much for months, or years, you're screwed. The best way to do it is to stay fit from a young age. It's a lot easier to keep it there than get it back.