Well...Here's my story...
I was always a fat kid til I hit about 14, grew a foot and a half or so, and was thin almost overnight, but never really changed my eating habits. When I graduated high school, I was 6'1" and about 180, not skinny, but not fat either. Over the next few years, it all caught up with me. Freshman 15 was more like freshman 40, and by junior year I was up to 260.
I don't really remember what flipped the switch, but I decided to make a change. That January, I started casually eating less, working out a couple times a week, and about March, I noticed I lost 20 pounds. I thought, "wow, I wonder where this could go if I really tried?", so I started counting every calorie and running every day. After a couple months, I was running 2 miles a day, riding a bike everywhere, and lifting about an hour a day (Oh the life of a college student! I wish I had that kind of time now). By Thanksgiving, I was down to 160, 100 pounds in less than a year.
I did good keeping it off for about two years, but then I got married, went to work full time, and grad school full time, and long story short, 3 years later, I've gained back every pound.
Funny I saw this thread today, as this morning I was so disgusted with myself, not being able to find a shirt that fit, that I decided this is the week I get back on the wagon. My goal is to be back down to 200 at least in time for the Warrior Dash in May. Wish me luck!
Best of luck! And to everybody trying to get healthier. I recently quit smoking and I feel better already. Been lifting pretty regular for about 9 months. Now if I can get my lungs back I should be gold. Ran 1.5 on my last fitness test in 10:44. Should go faster in March with clear lungs!