The food on airplanes is said to be far less appetizing than meets the eye. At least that’s what flight attendants tell the Huffington Post.

A flight attendant who has worked for a major American airline for seven years reveals to the “Huffington Post” that many employees bring their own food to work. The food for planes is usually prepared by one of the few catering companies and then transported to the various airports by truck.

She advises that water (and also coffee and tea) should be used with care. While bottled water is fine, tap water should definitely not be consumed on a plane. “It depends on how often the lines are cleaned,” she said, noting that tap water is also often used on airplanes to brew coffee and tea. “The problem isn’t so much in the United States as in other countries that don’t have similar regulations.” E. coli bacteria, which could lead to gastrointestinal diseases, have already been found in samples.

Another flight attendant, who has worked as a stewardess since 2015, advises avoiding salty snacks like nuts and pretzels. That leads to dehydration. This also applies to soups and pasta dishes, which are more salted for consumption in the air than on the ground. Alcohol consumption is also discouraged: alcohol has a negative effect on the body at high altitude. “The air pressure in the aircraft cabin is lower than usual,” explains Dr. Clare Morrison, MD at MedExpress, opposite the Huffington Post.

“This lower pressure means the body can absorb less oxygen,” she added. “This can lead to drowsiness or hypoxia. In other words, the lower levels of oxygen in your blood makes you look drunker in the air than you do on the ground after drinking the same amount of alcohol.”

Those who drink their drink on ice should not forget that these could be made from the plane’s tap water.

What: “Huffington Post”