A flight attendant says passengers should refrain from ordering a particular type of drink when flying, to avoid a "rough" time. The cabin crew member, who has kept her name anonymous, opened up about her experience of working for various airlines over 10 years.

During so, she revealed many do's and don'ts that passengers may want to consider.

Discussing drinking on the flight, the American flight attendant said people may want to think twice before ordering a sweet beverage.

"I would suggest not [drinking] anything sweet because it's really rough when you get on the ground," she said on the Other People's Lives podcast.

The cabin crew member did not provide further details, though Kezia Joy, a registered dietitian nutritionist and medical advisor at Welzo, explained why this type of drink can be problematic.

"Sweet drinks may be particularly impactful on passengers during a flight because air travel itself tends to disrupt the body's normal hydration and metabolic processes," she said.

"The cabin air is generally quite dry (low humidity), and this contributes to increased dehydration of both fluids lost by way of respiration and transdermal evaporation of sweat.

"Additionally, while sugary beverages will quench one's thirst, they are not as effective at hydrating as pure water.

"Therefore, passengers consuming sweetened beverages before landing may experience mild discomfort, fatigue and/or excessive thirst during longer flights," she added.

In recent years, it's also been claimed that many worry about drinking tea and coffee on flights due to the water used.

Water tanks on flights are meant to be cleaned and disinfected regularly, but poor maintenance can reportedly allow bacteria to develop.

According to the flight attendant, there should be no issue if passengers do opt for this drink of choice.

She said: "It really depends, so they clean the tank where the coffee is, where the hot water would be. It still is hot water."

Explaining why some travellers remain hesitant, she pointed to a past "epidemic" of E. Coli contamination in aircraft water supplies that left passengers ill.

"I think a lot of people still think that," she shared. "But listen, we drink coffee on the plane all the time and everything's fine.

"You know when they do [clean the tanks] because the water tastes like chemicals, it's really gross, but they do [clean them] yeah."

A different flight attendant however has urged passengers not to opt for tap water.

Sue Fogwell told Travel + Leisure: "I never drank the tap water. Coffee and tea are made with tap water, which comes from the airplane's water tanks."

As an alternative, she said: "If you want coffee, buy it in the terminal, [and] if you need a caffeine boost, ask for a Coke or Pepsi."