A FLIGHT attendant has revealed why you should never ask the crew to serve you coffee on the plane.
Madeleine Doyle, a 20-year veteran flight attendant explained why the drink annoys them the most when a passenger requests it.
She told Thrillist: "We all hate serving coffee - I'm not sure why this is such a thing for flight attendants, but it is.
"For all the things that set flight attendants off, it's passengers changing their minds about how they take their coffee.
"First they say they want it black, so we hand it to them black. Then they say, no, they want cream and sugar.
"It's all bad coffee anyway, what does it matter how you take it?"
That's not the only reason you should avoid it on the plane.
Caffeinated drinks having a similar effect on the body as alcohol during a flight.
Drinking coffee before a flight can cause frequent trips to the bathroom, with dehydration causing an increased need for the toilet.
Caffeine can also cause headaches and insomnia, which is not ideal if trying to sleep during the flight.
Kevin Kwan, the author of the novel Crazy Rich Asians, has also travelled the world and revealed why he never drinks coffee on planes.
As well as booze, Kevin avoids drinking caffeine too, saying: "I also don't take caffeine at all. I have my ritual."
Avoiding coffee can also help you avoid jet lag too.
Samantha Brown, who travels for a living as a TV host, said the key to avoiding jet lag starts days before travelling.
She told Travel + Leisure: "I try to limit caffeine a few days before I leave on a trip so it is totally out of my system when I land.
"I try to wait to have more caffeine until I'm about to collapse and that is when I allow myself to have a double espresso."
She continues: "The caffeine then hits my system so strongly because I am so depleted of it that I am able to go the rest of the day.
Here are five drinks you should never order on the plane.
A flight attendant has revealed how much water people need to drink to avoid jet lag.
