While any attempt to bypass travel sickness may seem like a futile effort to avoid the inevitable, there are a few things that will help you reduce your chances - if not totally avoid - getting sick on your trip & after you’re back to the grind.
take the red eye
If you're traveling to a different time zone, your best bet is to take a red eye flight - but make sure that you actually SLEEP on the red eye! Taking the red eye keeps your internal clock consistent so that you don't arrive to your destination already exhausted. This way, you'll be able to go to sleep around bedtime, and wake up when you arrive to your destination, allowing you to maximize your time doing the things you actually flew 7+ hours to do and see. Also, you'll already feel acclimated to the new time zone, and be able to bypass that horrible jet lag. Those who have trouble sleeping on planes should consider wearing eye masks and/or taking a natural sleep aid, like Melatonin or Valerian Root. Also, take a hard pass on the alcohol.
steer clear of germs
Especially on commercial flights, the cacophony of phlegmy coughs, incessant sneezing and gross sniffling from a congested cabin full of contagious passengers might seem like the end of the world - or at least your trip - but it doesn't have to be. Wash your hands regularly, keep hand sanitizer at the ready, wipe your face and hands with wet wipes at least a few times per flight, and consider (just consider) one of those face masks - because sometimes you need to look a little subpar to stay above it all.
This might sound obvious, but even if you're traveling to Bermuda in July, you might want to pack a sweatshirt or light blanket in anticipation of freezing cold airports, restaurants, flights and anywhere else the AC is unexpectedly confusing your tropical vacation for Antarctica. Even in the warmest climates, the evening temperatures can fall quickly, and there's no quicker way to catching a cold than being cold. Also, don't travel to Paris in December and try to trick your Instagram followers into thinking you were there in July by wearing a skimpy dress or foregoing a winter coat.
Regardless of whether you're exploring the Pantheon in the middle of summer or watching the Nordic lights in January, always stay hydrated. If it's freezing cold out, drink tea or hot water with lemon (my fave). If it's a boozy vacation, try to match every alcoholic drink with a glass of water or opt for spritzers that pair a little bubbly (water) with the most refreshing of alcohols.
sleep well and often
Sleep, sleep, sleep. If you're a busy person who likes to work hard, play hard and would rather sleep when you're dead, try again. Sleep is the best way to avoid sickness on your vacation, enjoy your vacation, and re-acclimate into your post-vacation life seamlessly. If you couldn't take a red eye, your destination was simply too far, or you couldn't sleep on the flight, take short naps until you can acclimate to your new time zone. Even then, make sure you're well rested, even if it means spending a little extra time in the hotel everyday, ordering room service and getting to sleep early one night, cutting out an early morning run or adventure to sleep in a few extra hours, or taking a nap everyday, try to fit sleep somewhere into your travel equation.