Caffeine Appears To Disrupt The Body’s Circadian Rhythms, Small Study Suggests.

They found caffeine can block cell receptors — molecular doorways — that let in adenosine, a message carrying chemical or neurotransmitter that promotes sleep. The same team did a study that showed when they stuck eight people out in the mountains without any artificial light, their body clocks switched over to send them to sleep at sunset and awaken at sunrise. The new findings may help explain why heavier coffee drinkers tend to be night owls, they said. It might lead to strategic ways to use coffee to fight jet lag — rather than simply throwing back a few triple espressos and hoping for the bes reports that caffeine appears to disrupt the body’s circadian rhythms, which explains why people who drink coffee at night cannot fall asleep. For example, “the amount of caffeine in a double espresso shifts this clock by 40 minutes.” When “combined with bright light,” the effect is “even worse,” the study (9/17) published Sept. 16 in the journal Science Translational Medicine suggests. http://www.nbcnews.com/health/health-news/heres-why-coffee-keeps-you-night-n428406