We often make assumptions about the things that make us lonely. But research shows that the amount of time you spend with other people, and the quality of our social skills don't really make a difference. So why is it that nearly half of the U.S. population reports feeling lonely regularly? Glad You Asked hosts Alex Clark and Christophe Haubursin set off to discover what causes loneliness, how it affects our health, and what to do to address it.