One of the least pleasant aspects of going to sea is the possibility of getting seasick. An individual's susceptibility to seasickness is highly variable. If you've ever had motion sickness when traveling by car, plane, or amusement park ride, you may be more susceptible to seasickness while aboard a vessel.

Yes, feeling sick on a ship—known as seasickness or kinetosis—is a completely normal physiological response that affects approximately 30% to 50% of people in rough waters. It is caused by a "sensory conflict" in the brain: your inner ear (vestibular system) detects the ship's constant rolling and pitching motion, but your eyes, looking at the stable interior of the cabin, signal to the brain that you are stationary. This disconnect triggers the brain's defense mechanism, often resulting in nausea, cold sweats, and vomiting. Most people experience these symptoms during the first 12 to 24 hours of a voyage, after which the body usually achieves "sea legs" through a process of habituation. Factors like age (children 6-12 are most susceptible), gender, and diet can influence the severity. Modern cruise ships use massive computer-controlled stabilizers that extend from the hull to reduce rolling by up to 90%, making seasickness far less common on large commercial vessels in 2026 than on smaller boats or older ships.