I’m An ER Doctor. Here’s The 1 Thing I Always Do When I Travel.

It’s not staying hydrated, eating well or even handwashing (although those are all important, too) ― when New York City emergency room physician Dr. Calvin Sun travels, his No. 1 priority is quality sleep.

There’s no denying that traveling has extensive health and mood benefits, but making sure you get proper rest while you’re away is key to enjoying them. It’s not exactly easy to do: A 2023 study found that only 18% of hotel travelers reported “excellent” sleep while they were away.

Sun knows sleep health is key, both from his medical experience and also from his weekends leading adventure travel experiences, including excursions in Antarctica, Africa, the Swiss Alps and Easter Island. He has traveled to close to 200 countries in the last 14 years. Those types of experiences are more enjoyable when you’re awake and happy, which is why he said he always focuses on getting good sleep before and during a trip.

Here’s what he does to ensure he’s well-rested enough to truly see the world while he’s away:

Regular bedtimes aren’t just for kids. “You can harness them to your advantage,” Sun said. “Make your schedule around it [so you can] be more awake and efficient to be able to do things and see things you want to.”

He begins adjusting his bedtime three to four days before travel: He’ll go to sleep earlier if flying east and later if flying west so he can adjust to the time zone changes.

If it’s one to three time zones different from home, Sun doesn’t stress too much about specific sleep planning. “Your body can adjust quickly,” he said. “But anything more than three to four hours ahead or before, and I’m a little more intentional.”

For eastbound trips, he prefers red-eye flights for easier in-flight sleep. He uses an app called Time Shifter to help navigate sleep and time zone changes, which he trusts as it’s based on NASA science for astronauts combatting jet lag. He also pays special attention to caffeine and melatonin timing, light exposure and darkness exposure.

Sun understands enjoying nightlife at your destination and having a drink on the plane. But he personally holds off on alcohol as much as possible because it can wreak havoc on quality sleep — and he says that means he doesn’t enjoy his trip as much.

“I don’t blame people for wanting a little nightcap before they sleep … It’s the allure of fancy travel…