Where do the carbon atoms that we are exhaling come from?

Question

Where do the carbon atoms that we are exhaling come from?

In: 5

Answer 1

They’re all from the food you eat! Carbs, fats, and protein all contain lots of carbon atoms. Your body “burns” the food fuel by reacting it with oxygen. Calling it “burning” is maybe more literal than you think – overall it’s actually the same chemical reaction as normal combustion:

fuel + oxygen —> carbon dioxide + water + energy

Your body does this reaction in a slower more controlled way than an open flame, with more steps that allow for collecting and using the energy. But it’s the same reaction. The resulting energy runs your body, the water is used as well, and the carbon dioxide is exhaled.