Why does jet lag affect us and how can we recover faster?

The answer

Jet lag occurs when rapid travel across time zones creates a mismatch between your internal circadian clock and the local light-dark cycle. The suprachiasmatic nucleus can shift only about 1 to 1.5 hours per day, so crossing multiple time zones creates a prolonged desynchronization affecting sleep, digestion, hormone release, and cognitive performance. Eastward travel is generally harder than westward because it requires advancing the clock (going to bed earlier), which opposes the body's natural tendency toward a slightly longer-than-24-hour cycle. Research shows that strategically timed bright light exposure (morning light for eastward travel, evening light for westward) is the most effective intervention. Melatonin supplements taken at the destination's bedtime, combined with avoiding light at the wrong times, can also accelerate resynchronization by 50%.