On average, a healthy person can hold their breath for up to a minute. 

After that, carbon dioxide in your blood starts to dramatically rise. 

Eventually, a reflex is triggered and if you resist the urge to let it all out, you pass out.

 And you don't know all the damage you could've caused.

 If you do the work, you can train yourself to hold anything inside without negative consequences. 

But most people don't have that discipline or time.

 They just bury it inside and hope it stays there. 

Don't do it. Let it out. Be loud. 

Make everyone hear you.

 Because if you don't, it will eat you up inside.