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Does Caffeine Cancel Out Melatonin?
Evening caffeine can delay the body’s own melatonin rhythm.[1]
Based on Burke et al., Science Translational Medicine 2015 · Updated October 10, 2026
Evening caffeine delays the body's own melatonin rhythm[1]
The caffeine in a double espresso, taken three hours before bedtime, delayed the body's own melatonin rhythm by about 40 minutes.
Avoiding evening caffeine may help with delayed sleep timing; in a small lab study, caffeine taken 3 hours before bed delayed the melatonin rhythm by about 40 minutes.
Source [1]Burke TM, et al. Effects of caffeine on the human circadian clock in vivo and in vitro. Science Translational Medicine. 2015. (PubMed)
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Sources
- Burke TM, et al. Effects of caffeine on the human circadian clock in vivo and in vitro. Science Translational Medicine. 2015. PubMed
This page is general information from the cited sources, not medical advice. If you take prescription medication, are pregnant, or manage a health condition, check supplement changes with a pharmacist or doctor.