What's even more interesting is that some of the medical gastroenterologists have devoted medical articles to this exact issue, from use as diagnostic clues to treatments.
Alot of it comes down to what we eat, and the specific types of bacterial flora that colonize our colons. Roughly 1/3 of people produce Hydrogen sulfide gas, while another 1/3 produce predominantly methane. Hence the statistic about 1/3 of us being able to ignite our farts is apparently quite plausible. Some people have extremely offensive odors (and aparently unique to the trained nose) due to malabsorption syndromes like celiacs or pancreatic failure.
Beano works well in terms of reducing the overall volume of gas, while large amounts of Zinc can taper the amount of Hydrogen sulfide gas (if you're a producer).
And completely non scientifically, I agree about farting in the shower....just something about doing that makes the stench 10x stronger and enduring!
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