While jet-setters brace for a summer of air travel mayhem, there’s another element to prepare for: the literal headache of traveling across time zones.

• Why it matters: Jet lag hits our sleep quality — and could seriously affect health, Axios’ Carly Mallenbaum reports.

“When we jet into a new time zone, our circadian rhythm is thrown out of sync,” says Rebecca Robbins, sleep researcher and assistant professor at Harvard Medical School.

• It’s particularly turbulent when flying through more than three time zones and staying in a new place for more than two days, according to the Centers for Disease Control and Prevention.
• The misalignment of our internal and external clocks can disrupt body temperature, melatonin secretion, blood pressure and heart rate, Robbins told Axios.

🔎 Zoom in: University of Massachusetts, Amherst research on animals suggests that shifting the time of day that we’re exposed to light and darkness can interfere with the formation of neurons in the brain’s hippocampus.

• That’s the process that supports learning and memory.
• Chronic jet lag is also linked to depression, heart disease, cancer and high blood pressure.

⏰ To manage jet lag, Robbins says get ahead of it.

1. Skip the redeye because you’re not likely to sleep well on the flight. But if you must land in the morning, wear sunglasses or wait until the afternoon to walk around in the natural light.
2. Shift your bedtime 15 minutes later or earlier each night — in the direction of your destination time zone — the week leading up to your trip.
3. Update your watch and phone to the time of your new destination as soon as you board the plane, and “start eating, drinking and living on the new time.”

🛬 Once you land…

1. Prioritize exercise. It helps you “stay attuned to the pattern of light and darkness in your [new] environment,” and can help reduce stress.
2. Avoid a heavy meal right before bedtime because it could keep you awake at night.
3. Only nap when necessary. She recommends 20 or 90 minutes at a time.

💊 Melatonin, a supplement (not regulated by the FDA), has grown in popularity to manage sleep disorders.

• Some studies suggest taking melatonin before sleep can reduce jet lag symptoms after a flight. It’s typically considered safe to use short term, but there’s insufficient data on its long-term use, and melatonin bottles can be mislabeled.
• Many experts only recommend using sleep aids as a last resort, and with a doctor’s approval.

📱 Go deeper: This app has bedtime recommendations to help you beat jet lag.

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Feast your eyes on this marvelous photo of the sun setting behind La Parroquia de San Miguel Arcángel in the Mexican city of San Miguel de Allende.

• Thanks to Finish Liner Bev K. for the submission!