Shift gradually to destination time

When traveling to a different time zone in late winter, you should gradually shift your light therapy exposure to match your destination’s dawn, not cling to your home schedule.

Your light therapy’s whole point is telling your brain when morning starts. If you’re flying east (say, NYC to London), your new dawn comes earlier. Start moving your light session 15–30 minutes earlier each day for 2–3 days before you leave, then keep it at the new time after arrival. Going west? Delay the session the same way. Don’t stay on home time—that just guarantees jet lag plus a confused circadian rhythm.

Late winter complicates things because daylight is short in both places. A travel-sized light box is worth packing. I like the foldable ones that fit in a carry-on—Luminette glasses also work and are easier to use on a plane or in a hotel. Avoid blue light too late if you had to shift your session to an odd hour; blue-blocking glasses can help if you’re doing light therapy at a local time that feels like afternoon to your brain but is actually morning at home.

One more thing: if you usually take melatonin with your light therapy, adjust that the same direction. Shift it with the light.

Your brain cares about the sun where you are, not where you left.