While eating healthfully and frequently, along with strength training and cardiovascular exercise, you can safely gain lean body mass.  In the dining hall, start with a breakfast focusing on eating whole grains, fruit, and a source of protein.  Adding peanut butter to your breads, hot cereal, and fruit is a way to add healthy plant fats and additional Calories to your meal or snack.  Adding yogurt to your cereal is an alternative to milk.  For example, oatmeal, yogurt, and fruit with a hard boiled egg on the side is a great way to get energized in the morning.

At lunch time focus on complex carbohydrates like brown rice, whole wheat bread and pita, peas, beans, lentils, and potatoes.  Add hummus, cheese, and vegetables to a whole wheat pita for a high protein sandwich.  Have a veggie soup on the side and add tofu and brown rice to add protein, vitamins, and minerals.  Don't forget your fruit at lunch as well.  End your meal with an apple with peanut butter, sunflower seeds, and raisins for more potent nutrients.

Explore your options at dinner time.  Be creative by mixing things up from different sections of the dining room.  For example, add noodles and beans to a soup to make your own minestrone.  Then, head to the salad bar and gather fresh veggies, tofu, cottage cheese, and sunflower seeds.   Look for a lean protein and cooked vegetables in one of the entrées.  If nothing is "calling you name", then mix it up!  Ask the grill chef to fix you a veggie burger or grilled chicken. 

Snacking between meals can be a good way energize yourself for long days of classes and activities.  Whole grain crackers, yogurt, string cheese, hard boiled eggs, trail mix, fruit, and veggies are all healthy snack ideas.   Snacking is especially important if you are exercising and working toward building muscle. 

Focus on adequate hydration to help your body stay healthy.  Water is the primary beverage of choice.  Secondary beverage choices include low fat milk and unsweetened soymilk.  Limit juices, sugary beverages, and sodas.

As far as exercise, lifting heavier weights at low reps is a good way to build strength and weight (from lean body mass, not fat).  You could talk to Ron Arnold, or a personal trainer at the Rec Center for more information, or to set up an individual exercise plan.