Helium Balloons Watch
but its not meant to be good for you!!
but very effective!!!
but I hear it's not good for your health...
So is smoking and drinking
However, it is dangerous in regards that you can displace the oxygen in your body, which can result in death if the person is unconscious for long enough (death of brain cells etc).
Edit: just read above messages. Okay. Got it.
It's hilarious though.