Why is chewing gum so popular? Many chew gum to freshen their breath and clean their teeth when brushing is not possible after meals and snacks.a Others find that chewing gum is relaxing and an aid to concentration. In fact, because chewing gum has been recognized to reduce tension and contribute to alertness, the U.S. armed forces supplied chewing gum to the troops in the first and second world wars and still include it in field and combat rations. Some drivers find chewing gum more effective than drinking coffee to keep them awake. People who are trying to quit smoking may find that chewing gum helps. It is also popular for satisfying the desire for a snack—at an average of less than ten calories a stick.