So my friend recently said the majority of flatulence is swallowed air. I said it sounded like facebook science as I'd never heard of air being swallowed as a cause for flatulence. We're ONLY talking about farts here, from the alimentary canal as the definition says, NOT burps.

So the problem is I've searched and found Aerophagia (swallowed air) but it seems to be a specific anxiety condition or a byproduct of poor eating technique (not chewing) and NOT a major contribute to the majority of anyone and everyone's flatulence. Then again that's how I read it, there is nothing that really says "the majority of flatulence is swallowed air" even in the people who suffer from swallowing air from anxiety or eating too much. If it's ever even specific it discusses belching.

So /sci/ can you give me any more information? True or false: the majority of farts are actually swallowed air. Tell me what you've heard, what you've learned, why this is stupid or makes sense, and feel free to cite anything because I can't get past gentle language and results explaining what Aerophagia is instead of if it causes farts.