Sleepwalking is much more common in the U.S. population that previously thought.

In a new study, published in the journal Neurology, researchers found about 3.6 percent of U.S. adults - about 8.4 million people - sleepwalk. What's more, almost 30 percent of adults said they've strolled while snoozing at least once throughout their lifetime.

Previous estimates of sleepwalking prevalence were around 2 percent, with U.S. estimates dating back 30 years since they were last updated.

"I would like to correct the impression that sleepwalking is rare," said study author Dr. Maurice Ohayon, professor of psychiatry and behavioral sciences at the Stanford Sleep Epidemiology Research Center in Palo Alto, Calif. "This is a huge number of people."

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