what she said. Start being more physical. Walk instead of drive.
park farther away from things when you have to drive. Admit to yourself
that to lose weight you have to TAKE the time to do things with your body;
like walking, riding, stretching, and exercising. if you don't take the time now,
you will lose it on the other end; in terms of shorter life span and shorter HEALTHY life span. you're young, you CAN do this.

You might read "Younger Next Year - Turn Back Your Biological Clock" by Chris Crowley

forget diets, they don't work. CHANGE YOUR LIFE. that's what's going to work.