Coffee is a universally loved beverage for its taste and, more importantly, its stimulant properties. Even though caffeine is understood to be a stimulant, there is apparently more to it than previously thought. Basically, when you drink coffee at certain hours, it can cause real jetlag by interrupting your circadian rhythm or body clock, BBC reported.
It was widely believed that caffeine simply stimulates brain cells that maintain wakefulness and suppress those which promote sleep. This thinking seems to be outdated. The circadian rhythm affects the whole body and not just the brain. When your body clock is disrupted the effects cascade to all cells including those in the liver, fat, and muscles, among many others, ABC News reported.
Therefore, drinking coffee "isn't just keeping you awake," said sleep researcher Kenneth Wright Jr., a professor with the Department of Integrative Physiology at the University of Colorado at Boulder. "It's also pushing your [internal] clock later so you want to go to sleep later."
Wright's research involved five people whose body clocks with relation to both light, a known factor in sleep, and caffeine were studied. Three hours before bedtime, a capsule with an equivalent of a double espresso or a placebo was administered. On average, a delay of 40 minutes in body clocks was observed. This is just half of the delay in body clocks to those under bright light.
Being out of sync with your internal body clock causes sluggishness the next day. The body feels sleepy and not prepared for physical activity or even eating. While people have known this for a very long time, this confirmation that caffeine works in this way is certainly new.
However, coffee before sleep is not necessarily a bad thing, as CBS News reported. Since different people have different body clocks, it might work for some to have coffee at certain times before bed. Another implication is that caffeine, in the right amounts and administered at the right times, can actually be the cure jetlag.
