Did you notice your metabolism slow. I'm 24 now, gained 60 pounds in the last 4 years. It's been awhile since I tried to lose any. I'm going for 300 by the time I'm 26. What I'm curious about is getting to 300 before I turn 30. If I'm still 300 when I'm 30 is there a good chance I could start piling on the pounds like end up 400 or so?