We’ve all been there after a long trip—staring blankly at emails, counting the hours until bed. Yet when 2 am hits, you’re still wide awake, mindlessly scrolling through Instagram, trapped in the grip of jet lag. That’s the price for crossing time zones too fast.
Our internal clock, or circadian rhythm, governs everything from sleep to digestion to hormones and uses light to maintain its natural 24-hour cycle. But when we land in a new time zone, and day suddenly turns to night, this rhythm is thrown off balance. Most travelers adjust within a few days, perhaps with the help of a melatonin pill. But in the meantime, jet lag
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