Human Respiration is Not a Source of Carbon Emissions

That's not a problem. The CO2 that's released by humans (and animals) is produced by metabolising carbon from food, and the food comes from plants that have been grown recently. During their growth, the plants have absorbed an equivalent amount of CO2 from the atmosphere. Even when eating meat, the animals are typically only a few years old and were fed on recently grown plants. In contrast, the cars run on fossil fuels that are hundreds of million years old.

 Human Respiration is Carbon Neutral

The very first time you learned about carbon dioxide was probably in grade school: We breathe in oxygen and breathe out carbon dioxide. Any eight-year-old can rattle off this fact. More specifically, the mitochondria within our cells perform cellular respiration: they burn carbohydrates (in the example shown below, glucose) in the oxygen that we breathe in to yield carbon dioxide and water, which we exhale as waste products, as well as energy, which is required to maintain...