A group of medical specialists has provided an answer to a dilemma that has faced fliers since the Wright brothers took to the air in 1903 - is it okay to break wind mid-flight?
The experts' recommendation is an emphatic yes to passengers - but a warning to cockpit crews that it could distract the pilot and risk safety.
The study concluded that anecdotal evidence that flying increases flatulence is not hot air, finding that changes in air pressure at altitude result in the gut producing more gas.
When Danish gastroenterologist Jacob Rosenberg encountered the unpleasant problem first-hand on a flight from Copenhagen to Tokyo, he enlisted some of the finest minds in his field to address the issue.
The result was an in-depth review of scientific literature on flatulence, looking at issues such as whether women's ones smell worse than men's (yes), what causes the odour (sulphur) and how often the average person passes wind every day (10).
The bottom line, according to the 3,000-word study published in the New Zealand Medical Journal, is that airline passengers should ignore the social embarrassment of breaking wind and "just let it go".
"[Holding back] has significant drawbacks… such as discomfort and even pain, bloating, dyspepsia [indigestion], pyrosis [heartburn] just to name but a few resulting abdominal symptoms," the study found. "Moreover, problems resulting from the required concentration to maintain such control may even result in subsequent stress symptoms."
The authors - five gastroenterologists from Denmark and Britain - said that while passengers may experience poor service from the cabin crew as a result of their decision, the health benefits outweighed negative impacts.
However, the cockpit crew faced a lose-lose situation.
"On the one hand, if the pilot holds back, all the drawbacks previously mentioned, including impaired concentration, may affect his abilities to control the plane," the researchers said. "On the other hand, if he lets go, his co-pilot may be affected by its odour, which again reduces safety onboard the flight."
The authors canvassed several solutions, including using methane breath tests to screen wind-prone passengers from flights, but rejected them as impractical.
They did, however, note that the textile covers used on seats in economy class absorbed up to 50 per cent of odours because they are gas permeable, unlike the leather seats in first class.
They suggested airlines could improve the odour-eating properties of seats and issue special blankets and trousers to passengers to minimise flatulence.
Air New Zealand declined to comment when asked if it would adopt such measures.