A lack of food isn't the only reason you get hungry. There are lots of emotional or non-physiological hunger triggers, such as stress, anxiety or even boredom. Sometimes, men eat because they're bored; the brain interprets that desire for stimulation as hunger.
The best way to beat this kind of pang is to wait it out and to find something else to do. One option is exercise, which occupies the systems of the body (including the brain) and gives them something to focus on besides food. Not only that, some studies suggest that aerobic exercise suppresses hunger by regulating appetite-related hormones like ghrelin and peptide YY [source: Stensel]. In other words, when you exercise, your body feels less hungry. Some other ideas for suppressing boredom-induced hunger include taking a walk, reading a good book or playing a board game with your family and friends; whatever your activity, the idea is to distract your brain from that sandwich (or whatever food it tempting you) long enough for the desire to eat to diminish.