I lost almost 60lbs while I was growing up..
Sorry hal, I'm not qualified as a dietician, but I did put myself on a diet that worked, and is still working well.
I would say it was my freshman year that I really got sick of my weight. I was about 5'9" and almost 200lbs, and looking at my family, it really disgusted me and gave me the motivation I needed to lose weight.
The biggest part of me losing weight was cutting soda out of my diet completely. Drinking water or iced tea was all I had to drink. I NEVER once excersized, never hit the gym or did any activities of that sort. I really just started cutting my food portions down slowly to where they really should be so that I wasn't starving myself into eating a lot. If I were to snack, I ate something somewhat healthy, usually a fruit. I made sure to eat a big breakfast to get my metabolism and energy up for the day and a decent sized lunch, and usually a lighter dinner, never snacking after dinner. All while doing this I was basically losing weight fairly quick. My body adjusted pretty quickly to my new eating habits and I was losing weight at a good pace.
Now I'm about 5'10" and I have been at a steady 145lbs for the past 3-4 years. Lowest I got was down to 138, but I was just a little too thin for my liking. Now that my metabolism has been this fast since I dieted I eat just about anything I want and my weight is steady. I stick to diet sodas generally, and I made a good habit of liking healthy food now. I used to hate a lot of vegetables and stuff that generally didn't appeal to me, but now I actually enjoy them.