I have little problem with what I eat in front of my colleagues because a) I do not fear at all what they think about something as silly as my lunch and b) I frequently go to lunch alone anyway. I like to go to the deli at a nearby supermarket and get chicken salad. More delicious and a lot cheaper than going to a restaurant. I could live on that chicken salad, and actually, I guess that's what I've been doing this week! Other times I bring a slice of meatloaf (or sometimes two slices!) and eat it throughout the day at my desk. Depends on my mood.