For some people they're always as smelly as rotten eggs, for others they tend to be odorless. Photo / 123RF
For some people they're always as smelly as rotten eggs, for others they tend to be odorless. Photo / 123RF
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It is a mysterious science: why do some farts smell worse than others?
Everyone farts between 10 and 20 times a day. And though it may seem like an embarrassing reality we'd rather not live with, each fart is a sign of a healthy digestive system.
However, no one fart is the same - and the smelliness can tell you something about your inner health.
Sometimes it may be loud and odorless, or smelly. Sometimes it's really smelly. Sometimes it's silent but deadly.
"Smelly odor is not bad, it's just a function of what you're eating and what your bacteria is doing inside your gastrointestinal tract. Everyone is different."
Asked if smelly farts are a bad thing, Dr Brand responds: "Nope. It just means you're eating food and digesting it well - and there's more room on the outside than on the inside."
What is a fart?
A large proportion of the gas we let off during the day is carbon dioxide, which is largely odor-free.
One per cent is hydrogen sulfide, generated by foods high in sulfur.
It can comes from the air we swallow or gas seeping into our intestines from the blood.
Flatulence becomes concerning to doctors if it is caused by a chemical reaction in the gut, or by bacteria in the gut.
What makes a fart smelly?
Smelly wind is generated when food is not processed properly - usually carbohydrates.
When carbs are not absorbed sufficiently into your intestines, particles sit in your gut and ferment.
"Foul smell just means the carbohydrates you consume are being malabsorbed - it's fermented," Dr Brand told Thrillist.
"Some people are methane producers, and some people are hydrogen sulfide producers - which causes flatulence to smell like rotten egg," Dr Brand told Thrillist.
"It's all a function of what you eat."
What food makes farts smell worse?
Alcohol
Beer is carbonated, as are some wines. And both contain yeast.
A blog on the wine news site Vine Pair explained 'wine farts' are largely created by the hydrogen sulfide (H2S) generated in the brewing process.
It creates, a 'rotten egg, sewage like' smell when not properly ingested by the body.