It's an issue that every flyer has faced: that sinking feeling when you notice someone's let one go mid-fight, and, worse, when you realise you yourself can't hold one in any longer.
Well, now a group of medics have published a report that says it in-flight farting is ok, harking back to that old saying: it's better out than in.
Danish gastroenterologist Jacob Rosenberg commissioned the study when he experienced first-hand the social minefield of letting off mid-air methane on a flight between Copenhagen and Tokyo.
He enlisted five top gastroenterologists from Denmark and Britain to produce the 3,000-word scientific review that was published in the New Zealand Medical Journal on Friday.
According to the Bangkok Post, it looked at issues like whether women's farts smell worse than men's (a resounding yes, who knew?), what causes the odour (sulphur) and how often the average person passes wind every day (10).
And, it's what we all expected, being at 35,000ft does make you fart more as changes in air pressure at altitude result in the gut producing more gas.
The study emphatically states that holding in the gas can cause health problems, reading: "(Holding back) holds significant drawbacks for the individual, such as discomfort and even pain, bloating, dyspepsia (indigestion), pyrosis (heartburn) just to name but a few resulting abdominal symptoms.
So passengers are free to parp as and when they feel like it. For pilots, however, it's more complex, with researchers suggesting a gust of wind could even affect the safety of the flight.
The study says: "On the one hand, if the pilot restrains a fart, all the drawbacks previously mentioned, including impaired concentration, may affect his abilities to control the plane.
"On the other hand, if he lets go of the fart, his co-pilot may be affected by its odour, which again reduces safety onboard the flight."
So if everybody's free to fart as they please, what could airlines to reduce the subsequent stench?
After noting that textile covers used on seats in economy class absorbed up to 50 percent of odours because they are gas permeable (unlike leather seats in first class), researchers suggested airlines could improve the odour-masking properties of the seats and issue special blankets and trousers to passengers to minimise mid-air flatulence.
According to news.com.au, the medics said: "The future frequent flyer may develop the ability to 'sneak a fart' by wearing charcoal-lined underwear thus experiencing a comfortable flight in harmony with fellow passengers."
They also suggested cutting down fibre-filled food on-board.
Do you think people should fart freely on flights? Or is just inconsiderate? Leave your thoughts below.
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