As a person whose had multiple food allergies my entire life, I know about the strife that comes with trying to find food that won't make you sick. By the time I reached 18 years, I had plenty of experience avoiding food I couldn't eat. I knew how to pack my lunch for school every day, order food at fast food restaurants, and purchase food that I could make into meals from the health food store. I thought that I had all the tricks up my sleeve that I needed to eat on my own in college.
Needless to say, I was sadly mistaken. Suddenly I didn't have the same amount of money coming my way, I didn't have a consistent mode of transportation as I couldn't drive, and I had little to no access to common kitchen appliances. I would get hungry and not be able to get food anywhere or make it for myself. Slowly I had to figure out a system where I could eat when I needed to. Since I had so many experiences and it took me a while to figure it out I figured I would offer some advice up to those who are also struggling with food allergies and a low college salary.
Research food options at your college.
This is especially important for those high school seniors applying for colleges. Make sure you look up what sort of dining establishments they have. Most colleges have some sort of cafeteria setting, of course, but see if they have special options for people with food allergies. Also, see what other places on campus have food because 1) you will get tired of dining hall food and 2) there will be times when you won't feel like going to the dining hall. On my campus, the three main places are either cafeteria style food, so I can only eat salads with my wheat allergy, a pizza place, and a fast food joint that's mainly wraps and sandwiches that I can't eat. Make sure that you know where you can get food and how you can get it.
Find a nearby health food store ASAP.
It is possible to buy gluten-free foods at Walmart and other grocery/super stores but having a health food store to go to will give you a variety and likely better prices. This will also probably not be within walking distance of your college so make sure you have a mode of transportation whether it's your own car or not, find a way to get places so you can replenish your food supply. The college store will likely not have what you need.
Stock up on "real" food.
When I first moved to college I only bought snack foods like chips and nuts and cheese sticks etc. And that worked for about a week. Then I got tired of dining hall food, didn't have time to go buy food in between classes and meetings and studying in the library, and wanted real sustenance. Meanwhile, my roommates would come home at 11 and make ramen as a meal. Man, did I envy them. When you can't eat ramen, college life is hard. There is no gluten-free substitute in terms of cheapness. However, there are ways to make cheap-ish meals that are also gluten-free. I eat a lot of rice cakes with dips on them. Also, frozen foods from the health food store are helpful when you don't have time to leave and buy food. My roomates also eat a lot of soup so that could work. My point is, you're going to want real meals so make sure you have the means to construct them in your room.
I hope these tips were helpful to those struggling with food allergies in college. Know that I and many other poor souls are going through the same frustrations as you.