It’s the holiday season, and you’re about to board that cross-country flight home or jet off to a highly anticipated vacation destination. You’ve packed your bags, passed through security, and quite likely, downed a good square meal (or loaded up on snacks) because goodness knows, whatever they serve you on the flight is going to be unappetizing. But with interminable hours of butt-sitting in your near future, are you sure you’ve eaten (or stashed) the best foods for the airplane?

Though we often grab something filling to tide us over on a long flight or prioritize travel-friendly snacks, there are factors at play for what makes the best—and worst—pre-flight foods, especially if that flight is going to last a while.

Substances in certain foods can promote GI discomfort, bloating, gas, dehydration, and anxiety—none of which you want to experience when confined to a metal bird hurtling through the stratosphere. Here’s a look at several foods to avoid before lengthy air travel and a few alternatives for smoother sailing.

Alcohol

Especially if you’re an anxious flyer, you may feel the desire to drink for a bit of relief before or during wheels-up time. But before you order that Bloody Mary from the drink cart, consider its effects on your well-being both in-flight and afterward.

“Alcoholic beverages are extremely dehydrating, which is only amplified when flying,” says registered dietitian Abbie Gellman, founder of Culinary Nutrition Cuisine and scientific advisory board member for Jenny Craig. “You could even feel hungover before you land just from drinking and being dehydrated while flying!” To prevent this unpleasant possibility, make it a virgin while in the air (or just stick to water as your best bet).

Coffee and Tea

“I just love using an airplane bathroom!” said no one ever. To minimize the number of trips to that tiny, uncomfortable potty box, consider cutting out coffee and tea. The caffeine content in these beverages isn’t doing your urinary tract any favors—and it doesn’t help your hydration status either.

“High amounts of caffeine can be dehydrating,” Gellman says. “In addition, too much coffee can be acidic and cause GI distress in some people, and nausea could be a side effect of high caffeine plus dehydration.” Those with travel anxiety may also want to take caffeine off the menu to keep from feeling jittery or on-edge during a flight. And if you plan on sleeping through the turbulence, caffeine should be avoided.

Energy Drinks

With tons of time on your hands during a long flight, it’s only natural to want to power through a pile of work… and maybe you turn to an energy drink to help you do so. But like coffee and tea, energy drinks contain high levels of caffeine (and, sometimes, other stimulants). One study found that consuming just one energy drink led to a dramatic spike in stress hormones—the last thing you need during an already-stressful day of air travel.

Spicy Food

So you flew to New Mexico, and the airport is your last chance to lap up that amazing red chili. Should you go for it? Maybe not. “Spicy food may cause GI distress, an upset stomach, and overall discomfort,” Gellman says. “Bland is often better before and during a flight.” Plus, nobody next to you wants to be smelling that food.

Salty Snacks

You kind of have to wonder what airlines were thinking when they made salted peanuts and pretzels their standard snacks. The high-sodium content of these freebies has a tendency to make passengers retain water. Water retention not only leads to feelings of bloatedness but can also aggravate edema—a painful swelling of the feet and ankles—which many people experience on a long flight. Especially if this health issue affects you while flying, just say no to salty snacks.

High-Fat or Highly Processed Foods

“Digesting food full of saturated fat and sodium is challenging at best when we are on the ground,” Gellman says. “If we’re 30,000-plus feet in the air, it becomes that much more difficult.” To feel your best, take a pass on the bacon cheeseburger and fries at the terminal café.

Beans and Broccoli

Under most circumstances, high-fiber foods like beans and broccoli make a great choice for your health—but this is one time you might want to skip them. “These foods may cause bloating and/or gassiness for some people, which could make for an unpleasant ride both for the person who consumed them and the surrounding passengers,” Gellman says. (We’ve all had the misfortune of being seated next to that person... or being that person.)

To avoid becoming a farting flyer, save the legumes and cruciferous veggies for after you land—when you may especially need them to ward off travel constipation.

What to Eat for the Long Haul

With these items off the menu, what should you actually eat before or during a long flight? A light meal with neutral flavors—like a salad, wrap, or grain bowl—can minimize the chances of feeling unwell in the air. And fresh and dried fruits, unsalted nuts, popcorn, granola bars, or trail mix are all better bets for snack options. And finally, don’t forget the water—lots and lots of water.

Expert-approved
READ THIS NEXT: 11 Travel-Friendly Recipes So No One Gets Hangry on Vacation