What do you mean by "We don't eat carbon"? All food that humans consume is mostly made out of carbon, hydrogen, oxygen and nitrogen. The carbon is indeed breath

What do you mean by "We don't eat carbon"? All food that humans consume is mostly made out of carbon, hydrogen, oxygen and nitrogen. The carbon is indeed breathed out in the form of carbon dioxide, but no animal is capable of taking carbon from the air and integrating it into their body.