Drinking coffee at night affects body clock, study confirms

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Are you thinking of grabbing that cup of coffee before hitting the sack? If you are, then maybe it's time for you to stop that habit. A new study confirms that besides being a stimulant, coffee can actually disrupt your body clock.

Health News reports that based on the study conducted by the University of Colorado, drinking coffee a few hours before bedtime can change or affect how the internal body clock works because the caffeine has a stimulating effect that keeps the body energized. Worst of all, a feeling similar to jet lag or sudden sluggishness may be felt the following morning.

Professor and sleep researcher Kenneth Wright, Jr. from the university's Department of Integrative Physiology, explains that coffee changes an individual's body clock by resetting it, making the individual prefer sleeping at a later time. This internal clock is responsible for setting biological rhythms like the "sleeping and waking up" cycles.

Business Standard writes that a small trial was done on two males and three females to check how their body will react to caffeine before sleeping. The participants were tested for 49 days under four conditions: low light and placebo pill; low light and 200mg caffeine pill that is dependent on weight; bright light with placebo pill; and bright light and 200 mg caffeine pill that is dependent on weight.

Professor Wright noted that those who took the caffeine pill with low light had a 40-minute delay in their body clock, as compared to those who took the placebo pill with low light. Furthermore, the researchers discovered that bright light can delay the body clock by 85 minutes, while bright light with caffeine pill provides 105 minutes of delay in the body clock. These results may explain why people who drink coffee and sleep late at night, wake up late as well.

While the results may suggest that it is best to avoid caffeine before sleeping, the researchers also raise the possibility of using caffeine to reset body clocks of travelers and avoid jet lag, Yahoo! Health News states. It is an intriguing theory but the study is small and may need further evidences before it can be considered as a standard, assistant professor from Stanford University Jamie Zeitzer shares.

The researchers believe that if caffeine will be used on travelers who cross time zones, it should be done judiciously.

The study was published in the journal Science Translation Medicine last September 16th.