267 at 18
156 at 21

I'm not sure of my weight so I'll go by pant size. At 17 I wore a size 18 and now at 24 I wear a size 26. Currently at my highest weight of 322

Lowest: 165 at 20
Highest: 258 at 25

Lowest: Around 130 when I entered college at 18 (in 1989 - ugh)
Highest: 230 in spring of 2008

In 1994, when I lived overseas and was happier, walking a lot, going out clubbing all the time...I got down to low 150's
In 1999, I went from 196 to 160 -- so that was the thinnest I got while trying to lose weight