Sure, it can be done - - but not easily - - You have to work at it eavery day, except for the occasional slip up.
I'm almost done now losing even more than that (90 pounds within a year, from 280 to 190, I'm 5'10", 37 years old.)
McD is a place to be avoided, all fast food ... lots of calories, not a lot of nutrients ... and you could be tempted to have Big Macs and fries, ruining your entire week of progress within a few minutes.
Anyway it's all about the calories you need vs the calories you eat ... so I calculated what you need based on the info you provided.
http://walking.about.com/cs/calories/l/blcalcalc.htm
You need approx. 2,850 calories per day now to remain at your current weight (moderately active, weighing 220, this would change if you drop some pounds or trained harder of course and you would need to calculate again in a month or two, I eat 2,700 every day now and I weigh 192 - - but I train hard every day too....)
If you only eat 2,350 calories per day and you do moderate exercise, you have a 500/day calorie deficit - - Do that 7 days in a row and that's 3,500 calories - - basically, you lose a pound that week - - do that 52 weeks in a row, give or take and that's your ultimate goal achieved, 52 pounds in a year. I'd suggest eating a lil' more even - - 2,600 calories but training really hard to burn off the excess. You can create the calories deficit with the diet but also the exercise - - Plus since you're young it should be easier than for older people too, you probably have access to a gym at school, no charge, all that good equipment is right there for you to use.
It takes a serious commitment to achieve this of course, you have to be 100% sure you are doing this no matter what, no cheating (or as little as possible since nobody's perfect) and training regularly too, at least 30 minutes 5 times per week, any sport/activity is good as long as you push yourself hard of course, I'm not talking about slowly walkin' to school or anything like that, it has to be hard to make progress, right ? When it gets too easy you make it harder, always push push push.
Ok, good luck on your journey. You can check out my 'Daily check in' to see what I've been doing for nearly a year ... many tips and tricks there ... I don't do Vanilla No-S so I have made changes to help me get through this without feeling hungry all the time ... especially before my training sessions. I believe more in the total number of calories for the day rather than the no snacking thing, but that's just me.
Cheers !
Marc
![Image](http://tickers.TickerFactory.com/ezt/t/wWchWdC/weight.png)