here is the deal
Ok ... I'm going to tell you all about the freshman 15 ... me and all of my 8 roomates gained the freshman 15, including one who is a cross country runner. This is what causes it ... drinking and school food. I'll start with school food, my school has a buffet style "commons" and then a fast food style "cx". Though the commons seems healthy, the biggest mistake always made is overeating. It's a big social place so while your sitting talking to friends you just keep eating. If you think about a meal you would eat at home, usually one plate full, and then compare it to what your eating there, you'll realize that it's much more. Then the cx type ... you order food by price given a certain dollar amount equals one meal, the bad thing is, this is all unhealthy food, and if your not careful it can be just as bad a mcdonalds. The way to fix this ... I lowered my meal plan to the minimum, forcing me to eat out of my house, we are lucky enough to have full kitchens, because I found my portions are much smaller at home then at school. If you live in a dorm with no kitchen, this is a problem because your more limited, I would still try to eat there more because it may still same you calories.
Next is the alcohol, it doesn't matter what you drink, it's all metabolized as fat. It's like trying to diet and then everytime you drink is like injecting fat right into your system. Doesn't help at all. SOmetimes no matter what you eat you'll gian weight because of how much you drink. The best thing I found to do is find ways to drink less. I know it's not healthy, but often I would just eat a REALLy light dinner so the alcohol had nothing to absorb into, allowing me to drink less then normal. For me, my freshman year I started out weighing 150 lbs, went all the way up to 178 and a year later am just now getting back down at 155. Exercise will help, but if your increasing your calorie intake more than your exercising off. So watch the school food, try to stick to ONE plate, and drinking two cups of water before you eat will fill your stomach a little, try to drink less per night, and don't come home and eat when your drunk, I bet that's where at least 5 of the freshman 15 come from.