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A couple of years ago, I was traveling across the Drake Passage to Antarctica when our ship hit a patch of 15-foot swells. Waves slammed against the vessel, causing many passengers to retreat to their rooms, nauseated. By afternoon, at least two-thirds of us were suffering from motion sickness. The others? To them, the rocking and rolling felt like just another day at sea.
“Everyone is capable of motion sickness,” says Dr. Kristen K. Steenerson, a clinical associate professor at Stanford University School of Medicine specializing in inner ear and balance disorders. “It’s just that everyone has different thresholds for how much motion exposure is stimulating enough to make them sick.”
For some, it might be the simple movement of an iPhone camera during a FaceTime call with an elderly relative. For others, it takes the pounding waters of one of the world’s most turbulent seas. Still others might need a week crossing the Atlantic to feel even slightly seasick—a form of motion sickness. Popular Science spoke with Dr. Steenerson to understand why some people are more susceptible to motion sickness and how to reduce its effects.
What is motion sickness, and what causes it?
Motion sickness is a temporary condition that can develop quickly, typically triggered by movement in cars, boats, planes, trains, and amusement park rides like roller coasters and Tilt-a-Whirls. Some people get motion sick on a playground swing; others on a surfboard. Symptoms range from nausea, cold sweats, and headaches to vomiting, pale skin, and dizziness.
Motion sickness usually arises from a sensory conflict or neural mismatch—when the brain receives conflicting signals from three key sources essential for balance: the eyes, the inner ears, and body sensors in joints, muscles, and tendons (known as proprioception, the body’s ability to sense its own movements). For example, typing without looking at the keys or knowing how much pressure to use when holding an egg.
“The brain takes different sensory bits of information from all three and then combines those together,” says Steenerson, “integrating them into one cohesive message.”
When what your eyes see matches what your ears detect and your joints feel, your body feels oriented and motion feels normal. But when these signals don’t align perfectly, your brain and nervous system become stressed.
“The brain gets conflicting signals and doesn’t know what to do, so it triggers a cascade effect, irritating neighboring structures in the brainstem and throwing everything off balance,” explains Steenerson. Your body then reacts to this sensory confusion by trying to purge any perceived toxins.
“There’s a theory that motion sickness evolved from people being poisoned,” says Steenerson, “because poisoning causes a sensory mismatch as well. The brain gets confused and says, ‘let’s try and get rid of everything just in case.’”
How common is motion sickness?
Motion sickness is very common. About one in three people are highly prone to it, though severity varies.
Age, genetics, and environmental factors like poor ventilation and strong odors (e.g., cigarette smoke) influence how severe motion sickness can be. Studies suggest that up to 70 percent of susceptibility is inherited.
“Kids are much more susceptible,” says Steenerson, “and women who are premenstrual, perimenopausal, or post-menopausal can also become more susceptible,” as well as pregnant women, due to fluctuating hormone levels, especially estrogen.
Generally, motion sickness is more common in childhood (ages seven to 12 are the most susceptible), less so in adulthood, and increases again in later years as the inner ear’s motion sensors degenerate with age. People prone to high anxiety or migraines also face higher risk.
There is also a form called sopite syndrome, characterized by intense drowsiness, mood changes like depression, irritability, and apathy. It often affects sailors, astronauts, and aviators exposed to long, repetitive motions—those who seem adapted to motion sickness but suffer persistent fatigue.
What can help mitigate the effects of motion sickness?
Though motion sickness is tough, many strategies can reduce symptoms.
“Many avoid eating because they think, ‘I’m going to get nauseated, I don’t want to throw up.’ It’s actually the opposite,” says Steenerson. Eat small amounts, but avoid heavy or spicy meals that upset your stomach. Avoid alcohol, which dehydrates and worsens motion sickness.
Focus on a stationary object when in a moving vehicle to reduce sensory mismatch, or minimize movement sensations. For example, sit in the front seat of a car rather than the back, choose a seat over an airplane’s wing near the center of gravity, or position yourself mid-ship on a boat near the waterline—the steadiest spot onboard. Avoid backward-facing seats on buses and trains, which can cause sensory mismatch; opt for front-facing seats instead.
If taking medication for motion sickness, take it one to several hours before travel. “If you’re already motion sick, you’ve missed your window,” Steenerson warns. Fresh air, ginger chews, and ginger ale can help by blocking nausea signals in the brainstem. Another trick is having touch points—like laying on a bed or pressing your head against a seat on a plane—to help offset confusion between eyes and ears.
Interestingly, listening to music can also help. “There’s a study showing over a 50 percent decrease in motion sickness when soft music is played,” says Steenerson.
You can also train your brain through habituation, the process of repeatedly exposing yourself to the motion until tolerance builds. For example, start by reading for five minutes in a car and gradually increase the time.
Managing, adapting, and adjusting
Whether you feel slightly dizzy stepping out of a car or are ready to vomit during rough Antarctic seas, motion sickness is real and common. But don’t let it stop you from taking that road trip or visiting your seventh continent.
“Most motion sickness probably comes from your brain,” says Steenerson, “so healthy brain habits do matter.” Rest well, stay hydrated, and arm yourself with Dramamine, ginger chews, and plenty of soothing music.
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