Why Do We Cough?

Conventional wisdom would have it that we cough when we are sick to “clear” our throats and lungs of bad stuff. We commonly think of mucus and phlegm as something we need to get rid of. Long before we knew of viruses and bacteria and germs of all sorts, we associated all that gooey stuff with the cause of our being ill. But it is part of the cure. Our bodies have evolved this complex stuff known as phlegm to engulf the germs that have taken root in us and it works best when it is inside of us. Making us cough is actually the evolutionary strategy of the virus to escape from us and move on to the next victim. We know that cold and flu viruses are spread by airborne droplets…of mucus spewed out when we cough. When we are told to “cough it up” we are the unwitting accomplices of our enemies. But what happens to all that goop if we don’t cough? It gets absorbed in our lungs, and swallowed into our stomachs where our immune systems can react quickly and target the invader to eliminate it. Even worse is the consequence of all that coughing. We do harm to our throats. And our lungs. When we have a tickle in our throats, clearing them and coughing is like scratching an itch. But just like scratching, when we do it too much, it leads to more swelling, not less. And more swelling, means as it does everywhere in our bodies, more pain. And more coughing. I often see patients in the office who have largely recovered from a cold but days and weeks later are still complaining of sore throats, frequent throat clearing and a persistent cough. As I explain the above scenario to them, I show them how to not cough, by swallowing, drinking, and coughing with a closed mouth or into their sleeve. Within a day or so they are often so much better that they don’t need any of those colorful cough medicines and lozenges and rubs that they have been fruitlessly trying.