Nothing at all. Balloons will pass normally through the digestive tract with no problems.
You'll choke and die
put them in a balloon tie the balloon and swallow it.
If you swallow a balloon you will most likely suffocate and die. This may sound a little over the top however it is likely that the balloon will wrap itself round your lungs and will disrupt your respiratory system. On the other hand, a balloon might block one of your vital arteries or might get stuck in your throat. If you swallow a balloon you should call an ambulance immediately.
When a balloon is poked with a pin, the sharp object creates a hole in the balloon's surface. As a result, the air inside the balloon rapidly escapes through the hole, causing the balloon to deflate quickly.
I suppose it depends on the size, but not a regular party size ballonn.
The balloon will either float or pop
The balloon expands.
Nothing happens
pain
You Die
you die
you die...