Why Do We Get Sick from Stress?

Imagine your body is like a castle. When you feel happy and relaxed, the guards are resting inside the walls. But when you get stressed, it is like an enemy army is approaching!

Your brain sends out loud shouts to tell all your cells, "Get ready for battle!" It pours out special juice called cortisol that wakes everyone up. This is great if there is actually a tiger attacking. But if you are just worried about a test or traffic, the guards stay awake too long.

Because the guards have been shouting and running around for weeks without stopping, they get very tired. They stop watching the gates carefully. Now, tiny germs that usually cannot sneak in can wobble right through the open gate. This is why you might catch a cold or feel sick even though nothing changed outside. Your stress turned your inside world into a place where germs love to play.