Eating healthy suggestions for a college student and resident?

I've been a resident in college for a little over four weeks now (Sunday it'll mark a fifth), and since then I've been even more concerned with healthy eating than before. Since my parents used to be in charge of what goes through one end of me, I trusted that the food they made was healthy for me, so eating healthy wasn't a big concern of mine up until I got into college. Now I'm fully in charge, so since I've been here I've been more of a health psycho than ever.

I've also ironically been eating far worse.

I've been consuming much more sugar and fat than ever, especially when I go to the cafeteria to eat with my buddies (the main reasons I eat there are 1. my buddies are there, and 2. I often get lazy to cook for myself especially considering that my dorm doesn't even have a kitchen of its own so I have to walk all the way to the one next door). It's easier for me to eat what seems healthier when I make it myself.

For example, I've since developed a pasta sauce recipe involving tuna, olive oil, capers, olives, oregano and a little black pepper to taste. Seems fairly healthy.

Problem is I only have access to the grocery store on Tuesdays since it's the only time a transport service allowing students to go to said grocery store is available (as residents, the least of us actually have vehicles of our own). This cuts down my options to purchase certain foods such as veggies or fruits since I cannot keep those for too long and thus must eat them right away.

Another problem is the inherent contradictions every single friggin' dietician in the world seems to have with respect to every other. Some say vegetable oils are bad, whereas others say they're good. Same applies to fruit juice, red meat, nuts, grains, so on and so forth, so I have no idea what actually IS healthy.

That said, I'm an underweight (I'm 110 lbs when I should weigh AT LEAST 130 lbs, but I always have been underweight) 20-year old male who can't gain weight (fat or muscle) for the life of him, I work out at least once a week (I know it's not a lot; I used to walk every day before school started) with a buddy who already has a diploma in natural sciences (so he has insight of how the human body works), I have little access to the grocer, I am Canadian-Italian so I'm used to eating a lot of grain, I do drink but on rare occasions and NEVER to get drunk (I genuinely enjoy the taste of wine; again, I'm part Italian), and I generally don't have any blatantly unhealthy habits (I've never smoked nor have I done any drugs, and I tend to sleep well).

My meal plan roughly translates to:

- At least one 156 ml can of V8 (veggie juice) a day.

- Nuts; right now I'm eating pistachios;

- Meat, albeit not much outside of cafeteria meals and cold cuts. I've been debating meat-eating ethics with myself lately too, actually.

- A lot of grains; oat or granola breakfast cereal, bread (I'm going to buy brown bread next), rice of different varieties and pasta (I've started buying whole-grain).

- Tuna once a week.

- Eggs.

- Fruit on occasion, less than when I lived at home; fruit salad (for variety), capers, olives.

- Veggies as much as possible; salad and veggies served at the cafeteria.

- A small glass of orange juice.

- Coffee or tea at most twice a day, usually once, lately not at all.

- Sauces; tomato, pesto, homemade oil-based pasta sauces, store-bought vinaigrette.

- Raw sugar (cane sugar, aka the best-tasting sugar), used in coffee (more) and tea (less).

- Peanut butter and blackcurrant jelly on occasion.

- Much less dairy than ever; a little milk in my coffee.

- A lot more soda; I always fall for temptation when eating at the cafeteria. I never buy it at the grocer.

One problem is that my diet is rather erratic; I've never "laid out" any sort of schedule so I tend to just eat whatever I'm craving that I have access to. I've only really eaten eggs once since I got here, for instance.

All that in mind, what do you suggest? I'm obviously not concerned with losing weight; I just highly value health.