Which direction causes worse jet lag?

Most people find it easier to stay awake later than to fall asleep earlier. Westward travel therefore lets the internal clock extend the day, while eastward travel asks it to shorten the day. Either direction can cause difficulty sleeping, daytime sleepiness, headache, irritability and concentration problems. The effect is also shaped by how many time zones you cross and your sleep before the journey.

Plan sleep and light around the destination schedule, not only the departure schedule. For an eastward trip, earlier sleep and morning daylight may help; for a westward trip, later evening activity and light may fit better. Keep meals regular, drink water, limit alcohol and use naps carefully. Allow recovery time before demanding work, and avoid driving when alertness is reduced.

Speak with a clinician if symptoms remain disruptive after a consistent local routine, recur after ordinary travel, or create a safety concern. Emergency assessment is needed for severe breathing problems, chest pain, fainting, sudden weakness, confusion or an abrupt severe headache.

Ask which light exposure fits your direction of travel, whether your current sleep pattern changes the advice, and how to manage alertness for a long drive or early shift.