>Correct, which is why we need to cut down on carbon emissions.
>
>Well, if you want to cut down on carbon emissions I suggest that you hold your breath for a while because you are exhaling CO2....

I would suggest a more practical (and useful) approach for the individual person - such as these:
http://cotap.org/reduce-carbon-footprint/

Responding with things like "hold your breath" is not helpful.