Your body clock may catch up faster on melatonin after flying east
In four small studies, clock hormones settled into local time faster or more surely on melatonin; in the lab, one 3 mg afternoon dose shifted the clock further than placebo.
What the study found
Clock hormones realigned better on melatonin in small flight studies
In four small studies after eastward flights, the melatonin and cortisol rhythms that mark the body clock realigned with local time faster or more surely on melatonin. In the lab, one 3 mg afternoon dose moved the clock half an hour further than placebo. The clock itself moved.
The caveat · Caffeine did the same in one study
Slow-release caffeine sped the hormones' return just as much in one of the studies. In a trial of 31 people whose days were full of irregular daylight, melatonin did not speed the body-temperature rhythm's shift. The two smallest studies, of 6 and 8 people, described no placebo group.