More people are lonely than ever before. Studies show that one in five Canadians identify as being lonely. Loneliness is more than a feeling of occasional solitude – it’s a prolonged feeling of perceived isolation. While long seen as being bad for mental health, loneliness is now recognized as being physically harmful too. It's being called the silent killer – considered by some experts as being more harmful than smoking 15 cigarettes a day. In fact, loneliness is now linked to heart disease, depression, obesity and other life-threatening conditions. So why in our highly connected world are we so lonely? And what can we do about it?