Many people treat themselves to a drink onboard when they fly. Some people prefer to stay hydrated with water or a soft drink, while others might like to indulge in an alcoholic beverage.

One popular beverage you might have seen people order is tomato juice. According to SWISS, tomato juice is "the cult drink par excellence on planes" - and it might not be something you see people ordering if you go to a regular bar on the ground. So why do so many people order it up in the sky? It turns out there's a clever reason.

Taking to TikTok, cabin crew member Michael de Vos took to KLM's TikTok page to ask: "Ever wondered why so many people order tomato juice onboard? Well, that's because our taste perception changes at high altitudes, making our tastebuds more sensitive to umami flavours.

"And even engine sounds in the cabin can affect your taste. And that is why the tomato juice tastes more vibrant and satisfying at cruising altitude compared to other drinks."

Michael added: "Some people order tomato juice because it contains salts, which makes them go less often to the toilet. But the tomato juice also has other benefits, like it's packed with vitamins, antioxidants, minerals, like vitamin C and potassium."

Explaining the phenomenon further, nutrition coach at OriGym Centre of Excellence, Alice Williams, told Express.co.uk: "During a flight, two main things happen to the air: the pressure increases and the humidity drops. This combination of low pressure and dryness is ultimately what makes your taste buds change.

"The dryness in a plane also reduces your sense of smell. Since smell actually makes up a large part of how we taste food, this will also affect how food tastes in the air."

Alice recommended people choose foods full of umami flavours, also known as savouriness, "since umami is not affected by flying". Tomatoes is a good source of umami flavour, "which is why many airlines offer tomato juice as the option of a complimentary drink on their flights," she added.

It's believed an estimated one million litres of tomato juice is served on flights around the world every day.

In the comments section people were fascinated to learn about why tomato juice tastes better on planes. One person wrote: "For years i have only been craving tomato juice on the plane which is crazy bc I normally never drink it."

Another added: "I always order tomato juice, because it’s the only savory juice and I’m not craving sugary drinks."

And a third said: "Tomato juice is my travel drink and i always wonder why it is more appealing in the air! Now i know."