What causes motion sickness—and how can you prevent it?

Travelling by boat, car, or even through virtual reality can make some people queasy. Experts weigh in on what to do about it.

By Jennifer Barger
Published 5 Jan 2023, 10:34 GMT
Shaky views like this one seen during a car ride in London, England, are notorious for ...
Shaky views like this one seen during a car ride in London, England, are notorious for causing motion sickness, a common plague for many travelers.
Photograph by Patrick Zachmann, Magnum

For some travellers, a catamaran sail off Oahu, Hawaii, or a camel ride through the desert in Morocco isn’t an enviable vacation experience. It’s an encounter with nausea, dizziness, and cold sweats.

Motion sickness like this can happen to almost anyone, including children and dogs. Studies suggest that more than half of all people who ride in cars experience carsickness. Recent surveys of members of the Indian Navy, Icelandic fishermen, and South Carolina marine biologists indicate that up to 80 percent of individuals who work on boats get seasick sometimes.

“We’re even seeing cybersickness now, with people looking at their phones when riding in the car or wearing glasses for a 3D movie,” says Andrea Bubka, a professor of psychology at Saint Peter’s University in New Jersey, who has extensively studied motion sickness.

Here’s why motion sickness happens and what travellers can do to prevent it.

What causes it

Scientists aren’t sure why some people feel nauseated the second they step on a boat, while others can blithely read long novels while riding in the backseat of a car. But they have a few theories.

Many scholars believe motion sickness is caused by sensory conflict, a discrepancy between what people see and what their bodies are experiencing. “Human beings did not evolve to travel in space shuttles and use virtual-reality video games,” says Marcello Cherchi, a neurologist at Northwestern University’s Feinberg School of Medicine.

Sensory conflict happens when your body feels the heaving of an ocean ferry or the jolting motion of a bus winding through the mountains and your eyes, ears, and other senses can’t catch up. This results in symptoms like a dry mouth, dizziness, upset stomach, or a pounding headache.

However, other scientists believe that people get motion sick because they don’t instinctively change how they sit, stand, or walk in a moving mode of transport. That disconnect causes you to feel ill. 

Patricia Cowings (standing), a U.S. psychophysiologist who has extensively studied motion sickness, works with a test subject.
Photograph by HUM Images, Universal Images Group, Getty Images

One of the biggest proponents of this “postural stability theory” is Tom Stoffregen, a professor of kinesiology at the University of Minnesota. “On a boat or plane, you have to learn to move differently—like sailors who get their ‘sea legs’ after a few days,” he says. “The key is physical control of your body, and some individuals adapt more quickly than others.”

Genetics might play a part, too. A 2015 study of 480,000 customers of DNA-testing company 23andme identified 413 genetic markers—many related to balance or eye, ear, and cranial development—that could make an individual predisposed to motion sickness.

Preventing motion sickness 

The easiest way to combat motion sickness is to prevent it from happening in the first place. Hydrate and keep fresh air flowing while traveling, either by opening a window in the car, turning on the air vent above you on the plane, or heading to the deck on a cruise ship. 

“And be careful what you eat when you travel,” says Bubka. Anything that upsets your stomach on dry land—eating too much (or too little), drinking excessive amounts of alcohol or caffeine—could be amplified by motion. 

“Do everything you can to be sure your view isn’t obstructed,” says Natascha Tuznik, a doctor who specialises in travel medicine at the University of California Davis. “Look at the horizon if you’re out to sea and sit in the front seat of the car where you can see the road and what’s coming.” Closely watching what’s coming helps your eyes and inner ears sync more quickly with other bodily functions.

Avoiding triggers and anti-nausea training

Some research suggests that doing physical or mental exercises could help humans train themselves to be less motion sick. The Puma Method, developed by a flight surgeon to serve airsick pilots, uses yoga-like stretches and angular movements to build up anti-nausea conditioning. A 2020 study at the U.K.'s University of Warwick found that, after doing 15-minute visuospatial training exercises (finding hidden objects in puzzles, folding paper), many subjects didn’t get sick when taken for car rides. 

Commuters walk through a New York City subway station in 2017. Any form of transport—from trains to planes to boats—can induce motion sickness in humans.
Photograph by John Taggart, Redux

“The advantage is that these approaches don’t require medication,” says Cherchi. “The disadvantage is that they can entail considerable discomfort, at least initially.”

People prone to motion sickness can also practice “trigger avoidance,” steering clear of activities that make them bilious. If long bus rides make you turn green, rent a car instead, then sit up front or drive yourself. Those prone to seasickness should take flat-water river cruises or choose larger oceangoing ships with smoother rides. 

Medication—or gadgets—might help

Another way to combat travel-related nausea? Use an over-the-counter motion sickness drug (such as Kwells) which often work by affecting the way movement is perceived by parts of the inner ear, which can reduce nausea and have a calming effect.

However, such medicines only work if used a short time before you set sail or board that flight. Such drugs can also make you groggy, and many people have health conditions that preclude their use. Stoffregen advises travellers who don’t want to take pills to try ginger chews or gingersnaps instead. “There’s well-documented evidence that a little bit of ginger can significantly reduce nausea,” he says.

Multiple gadgets promise to help with motion sickness. Pressure-point wristbands, which rely on acupressure principles, come in models from inexpensive and basic to high-tech and high-priced. Wacky-looking anti-nausea glasses also came to market about two years ago, sporting liquid-filled frames and four round, glass-free lenses. The idea is that the liquid in the specs shifts as you move, creating an artificial horizon. 

While many users report feeling better when using these devices on planes, trains, and automobiles, studies have yet to support their efficacy. “Still, if there’s a placebo effect, and you don’t get sick, then I don’t care about the science,” says Stoffregen. “It’s money well spent.”

Jennifer Barger is a senior travel editor at National Geographic. Follow her on Instagram.


Explore Nat Geo

  • Animals
  • Environment
  • History & Culture
  • Science
  • Travel
  • Photography
  • Space
  • Adventure
  • Video

About us


  • Magazines
  • Disney+

Follow us

Copyright © 1996-2015 National Geographic Society. Copyright © 2015-2023 National Geographic Partners, LLC. All rights reserved