What Causes the Freshman 15?

What's Behind New College Students' Weight Gain

young woman weighing herself on stand-up scale
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It’s hard to be an incoming freshman and avoid hearing about the dreaded "freshman 15," the roughly fifteen pounds that many incoming freshmen tend to gain during their first year in college. While the poundage doesn't always exactly ring in at fifteen, the tendency to gain is significant enough to earn itself a lasting title.

First, it's important to note that this specific amount of weight gain isn't common to everyone. Some people gain more weight, some less, and some gain no extra weight at all or even lose pounds when they leave home for college for the first time. However, it's a common enough experience that it has earned a nickname that has endured through several decades, and is something to be aware of so it can hopefully be avoided.

What causes the notorious weight gain experienced by new college students? How can it be avoided? Let’s explore some of the underlying factors at play in the freshman 15:

New Eating Habits

When you’re living with parents and going to high school, many of the details of what, when and how much you eat are already planned out for you. Getting to college and having unlimited choices (and limited cooking experience) can make a diet of fast food, chips, soft drinks and pizza at 3 a.m. commonplace. Several weeks of this can cause quick weight gain.

Eating While Studying

Many new college students find themselves in a position of doing less studying during class time (under the watchful eye of a teacher), and more studying on their own time, when they can mindlessly snack on junk food for hours without anyone noticing. If you find yourself doing this, stop and think about what you’re really doing: eating large amounts of unhealthy food, when you wouldn’t normally be hungry, and not burning it off. This is not a good thing.

Eating Late at Night

Closely related to the eating-while-studying phenomenon is the eating-late-at-night habit that many incoming freshmen develop. You may naturally find yourself staying up later to study or party, and hunger may sneak up on you. The main problem with late-night eating is that you don’t stay awake long enough afterward to burn off the calories, and they end up being stored as fat.

Eating Snack Food

Often, the most convenient late-night food is fast food. In fact, fast food is a convenient choice for any time of day. If you’re not used to cooking your own meals or focused on making healthy choices when you buy your meals, it’s easy to fall into a diet of burgers, fries, and deep-fried nuggets, supplemented with chips and soft drinks. If you want a real scare, check the nutritional information on these foods!

Emotional Eating

College life comes with many changes and challenges, including difficult classes, new relationships, and homesickness. Many people deal with emotional stresses like these with emotional eating, which includes eating when you’re not hungry or filling an emotional void with food. If you find yourself becoming an emotional eater, it’s time to read this article on how to stop emotional eating, before you get closer to gaining the freshman 15.


Yes, many college students drink —- even freshmen. This contributes to the freshman 15 in two ways. Alcoholic drinks tend to be high in calories. Additionally, alcohol can deteriorate muscle tissue, which lowers your overall metabolism. So, in case you needed them, now you have more reasons to stay away from binge drinking.

Not Enough Exercise

Sure, trekking from class to class can be a workout. But it's not enough to keep you trim. Many college students find themselves busier than they were in high school, so there's less time to commit to regular exercise or be involved in other physical activities. This can be a big factor in the 15.​

You’re At That Age...

Many freshman 15 factors are under your control, but this one isn’t: your age. During the middle school and high school years, most teens are growing pretty quickly and staying active. The college years, however, generally occur in the first years of adulthood, when most of a person’s physical growth is complete and some lifestyle habits may start to change. This can contribute to the other factors that cause weight gain, causing many people to start putting on weight for the first time in their lives. This is the perfect time to start developing habits that will help maintain a healthy adult body for years to come.

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Article Sources

  • Vella-Zarb, R., Elgar, F. "Predicting the 'Freshman 15': Environmental and Psychological Predictors of Weight Gain in 1st Year University Students". Health Education Journal. 321-332, 2010.