What causes allergies and how do they impact the immune system?

Allergies happen when your immune system gets confused and overreacts to something harmless, like pollen or chocolate.

Imagine you're playing in a sandbox, and suddenly a big, bumpy rock falls on your foot, that’s the first time you see it. You might yelp and jump back, but you’re still okay. But if that same rock keeps falling on your foot every day, you’ll start to get really upset, maybe even cry. That's like what happens with allergies.

When something like pollen or pet dander enters your body for the first time, your immune system thinks it’s a danger, like that bumpy rock. It sends out soldiers (called white blood cells) to fight it off.

But if you see that same thing again and again, your immune system gets too excited. It sends way more soldiers than needed, causing symptoms like sneezing, itching, or even a runny nose, just like how you might cry after that rock falls on your foot several times.

These overexcited soldiers cause extra inflammation in your body. That’s why you feel stuffy or itchy, your body is trying to push out the "invader" (like pollen), but it’s making a big mess while doing it!