How Your Immune System Actually Works

Our friends and family think they understand their immune system because George Carlin explained it to them in the 90s:

Where did this sudden fear of germs come from? What do you think you have an immune system for? It's for killing germs. But it needs practice. It needs germs to practice on. If you kill all the germs around you, and lead a completely sterile life, then when germs do come along you're not going to be prepared. What are you gonna do? I'll tell you what, you're gonna get sick and you're gonna die and you're gonna deserve it because you're f-ing weak and you've got a f-ing weak immune system.

George Carlin was right about a lot of things, but he was wrong on this one.

(He got plastic wrong, too.)

Unfortunately, this part of his 11th HBO standup special became permanently lodged into the American cultural memory. I only saw it once as a kid, but it stayed with me for the rest of my life.

Not even AP Biology could dislodge it.

I, too, used to think you built your immune system up by exposing yourself to harmful germs. How could the great prophet George Carlin be mistaken on something that made so much intuitive sense, especially when you dropped a few f-bombs in there? I also thought it was a good thing to exercise your way through a cold. Then I opened myself up to the possibility that I was wrong.

In the words of Carl Sagan, I'd been bamboozled.

Every winter throws the equivalent of a pandemic at us now, and we’re cruising straight into another full one that everyone seems eager to blame on the incoming administration. Sure, they’ll do a horrible job. But so did the last administration. For all the talk about “preparing for the next pandemic,” most global health agencies and news outlets won’t even correct misinformation about immunity debt they helped promote when it was politically convenient.

It’s not rocket science to understand that preparation requires more than quelling outbreaks in animal populations. It requires an educated public that understands how their bodies fight pathogens. We live in a fundamentally different era now, one where each of us has to practice better scientific literacy.

Maybe you already know how your immune system works, but you’d like someone to sum it all up in a way that helps you articulate the details when your friends and relatives bash you for protecting yourself.

So, where did this idea come from—it’s good to get sick?

It has a history.