What does helium do if you breathe it in?

Answer 1

from what i know about helium; it is lighter than air or the oxygen we breathe so it sits higher in your lungs. Therefore when you exhale it passes through your vocal cords faster which is why your voice is a higher pitch. If you breathe too much Helium in you will become light headed because you aren't getting the oxygen your cells need. An example of a different gas is xenon which is denser and heavier than air. Therefore when you breathe it in it sits at the bottom of your lungs and takes longer to pass through your vocal cords and makes your voice much deeper. It's pretty interesting however xenon is very expensive.