Is there any way you can bring an insulated lunch bag with you to work? You could pack things like carrots with ranch dressing (light or low fat, of course) for a healthy, vitamin-packed snack.
You can also pack a sandwich for lunch with extra lettuce (use more spinach than iceberg lettuce -- spinach contains more vitamins, iceberg lettuce is mostly water.) Pile your sandwich high with more vegetables and less cheese and sauces like mayo.
If you like avocados, you can also add them to sandwiches, salads, our just eat them on their own (just scrape the brown part off the top -- everything underneath will be fine to eat.) Avocados add a nice consistency to meals, I even use them to replace salad dressings. Avocados are also an excellent source of healthy dietary fat.
Veggies can also be snuck into many recipes. One of my favorites is adding broccoli, cauliflower, bell peppers, onions, and mushrooms into my spaghetti sauce. It adds a lot of texture and tastes great while providing excellent vegetable nutrition.
Another thing about spaghetti -- ditch the high carb/high calorie noodles and replace them with spaghetti squash. Just cut the squash in half, gut it like you would a pumpkin and place the two halves face down on a cookie sheet with foil and cook for about 30 minutes. Let it cool then take a fork and make "noodles" by dragging a fork along the inside of the squash. You can have a huge plate for just a fraction of the calories that you would be getting with real spaghetti noodles.
Other quick tips:
Switch from regular white potatoes to sweet potatoes. Sweet potatoes contain tons of vitamin A and fiber(keeps you feeling full). One way I like to prepare them is baked with a little bit of butter and cinnamon...very yummy. They also make good baked french fries -- especially dipped in ketchup.
Tomatoes can be added to almost anything to add an extra serving of vegetables to your day.
Go for leafy green vegetables. They provide more vitamins than lighter, mostly water-packed vegetables like iceberg lettuce.
Asparagus and brussel sprouts are delicious and great sources of vitamin C.
You definitely need vegetables every day to live a healthier life, but fruit is just as important and is easier to take with you on the go. Strawberries, apples, pears, oranges, etc. Try to avoid dried fruits as they provide a lot of calories per serving(a very small serving at that) and they often have a lot of extra sugar.
I hope this helps! For more information on healthy diets go to www.choosemyplate.gov
Sorry if all this is a little overwhelming. I am studying to be a dietician and all this is just so interesting to me. I hope you become interested in it to, you will learn to love foods you never even knew existed and you will feel so much better!