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Caffeine and Sleeping Patterns: Is that cup of coffee really helping you to be more efficient?


Ellie Conser




Students use caffeine to stay awake, complete their work, and study, in hopes of achieving academic success.  Busy adults use caffeine for that extra “boost” in the morning, to help them get through the day and be productive.  People consume caffeine in order to alter their body’s natural need for sleep, often without regard to the consequences it has on their sleeping patterns, and in turn, their daily function and overall health.




Caffeine is a type of drug called a stimulant, found in coffee, tea, many soft drinks, and chocolate.  It affects the nervous system, altering chemical reactions in the brain, causing those who consume it to feel more energetic, alert, and productive.  Physical symptoms experienced by those who use it include an increased heart rate, muscle tremors, headaches, and difficulty sleeping.  ( 


It causes chemical reactions that:

-       Increase dopamine levels, resulting in a pleasurable feeling.

-       Block adenosine absorption.  Adenosine is usually absorbed by receptors in the brain and causes sleepiness by slowing down nerve cell activity.  When these receptors are blocked, a person does not experience these sleepy feelings, and nerve cell activity increases.  

-       Pump adrenaline into our systems, causing a temporary energy boost.  (




Sleep is essential for healthy functioning and occurs in several stages or patterns.  When a person falls asleep, their brainwave patterns slow down.  As the brainwave patterns get slower, sleep gets deeper.  The two slower brainwave patterns include theta waves and delta waves, which are followed by a period of REM (Rapid Eye Movement), in which brainwaves speed up to nearly awake levels.  REM is the period in which individuals experience muscle twitching, a back and forth movement of the eyes, and dreams.  During a restful night’s sleep, a person receives both REM and NREM (Non-REM) sleep, and experiences between 3 and 5 REM cycles.  sleep-stages.gif



Sleep deprivation occurs when an individual does not get enough sleep, or when the quality of their sleep is poor.  Immediate consequences of sleep deprivation include decreased attention and alertness, memory problems, clumsiness, and injury (including car accidents).  The results of long-term sleep deprivation include depression, heart problems, obesity, high blood pressure, and memory loss.  (


Caffeine and sleeping patterns

Various online, health-related sources seem to agree that caffeine causes disruption of sleep patterns, sleep deprivation, insomnia, and fatigue.  Consuming caffeine has been said to delay sleep onset, reduce total sleep time, alter normal stages of sleep, and to decrease the overall quality of a person’s sleep.  The extent of these alterations depends on the time of day the caffeine is consumed, the amount consumed, and an individual’s sensitivity to caffeine.  These health-related sources aim to inform those interested or concerned as to how caffeine impacts one’s health and sleep, and to guide them in making beneficial health choices. 





Various distributors of caffeinated products proclaim its beneficial effects without accounting for its consequences past initial consumption.  5-Hour Energy claims to provide “Hours of energy now…[and] no crash later” (, while Red Bull’s website says that, “Caffeine is known for its beneficial effects on mental and physical functions.  It has been shown to improve… reaction speed, alertness and concentration” (  Companies like Red Bull and 5-Hour Energy are presenting this information only to further the success of their companies and to encourage consumption of their product.  They do not provide any testimonials, studies, statistics, or evidence that their products are without problems. 


Scientific Research and Studies on the Topic


Numerous studies have been completed, and numerous papers compiled, in order to analyze the effects of caffeine on sleep and sleeping patterns.  The resulting information provides a scientific explanation of how caffeine impacts the body, including how it affects sleeping patterns and overall health.


A study done by Paterson (2009) sought to determine the effects of caffeine on sleep patterns in rats, aiming to apply the results to human behavior.  Results from the study indicated that caffeinated rats experienced a much lower quality of sleep; although they experienced the same number of sleep cycles, the relative lengths of these stages was unfavorable.  Consumption of caffeine resulted in a reduced delta power sleep, less time in NREM, more time awake, and an overall less productive sleep.  Results from this study also determined the effects of caffeine on sleep to be dose dependent, meaning that the more caffeine a rat consumed, the stronger the alteration of their sleep. 


A paper written by Pollack (2003) provided similar results, concluding that consuming greater amounts of caffeine leads to shorter sleep duration, longer awake time, and increased sleep during the day, or napping, in adolescents.  The paper stated that caffeine changes “the temporal organization of slow-wave and rapid eye movement sleep”, and is so disruptive to sleeping patterns that it is often used to model insomnia in healthy individuals.  Pollack also drew associations between regular consumption and tolerance or dependence, which often results in a type of physical and mental withdrawal in the absence of consumption.  Unlike the study conducted by Paterson, however, Pollack concluded that caffeine can have positive or negative effects in terms of health, behavior, and mental state, depending on the individual, the quantity consumed, and the duration of consumption. 


Not only does caffeine consumption have negative consequences for adults and adolescents, but also negatively impacts children.  In a paper written by Mindel (2009), caffeine was determined (once again) to delay the onset of sleep, and to cause a shorter sleep duration and poorer quality of sleep in children aged 0-10.  Because sleep is the time in which body restoration and growth occurs, the effects of caffeine consumption at a young age are especially problematic, in that a person’s younger years are most critical to their growth and development.  Caffeine intake should be monitored cautiously, especially at young ages. 


Should you consume caffeine? 


As in making any decision, an individual should weigh the benefits and consequences, keeping in mind that everything is okay in moderation.  Although caffeine provides the consumer the immediate satisfaction of feeling more energized and motivated by stimulating brain activity, this brain stimulation carries over, undesirably, into sleep.  Caffeine disrupts normal sleeping patterns, allowing the consumer to stay awake longer by sacrificing the duration and quality of their deep sleep.  Poor sleep prevents the body from being fully restored; leaving a person to feel fatigued the following day.  This can in turn cause them to reach for another cup of coffee, and place them in a negative health pattern.  Drinking a cup of coffee every once in a while, when needed, can be beneficial to productivity, and will not affect a person’s overall health.  Regular consumption, however, can be detrimental when it results in tolerance or dependence, leaving an individual in a state of less-than-perfect health.  In order to experience good health, individuals should make efficient use of their time and get an adequate amount of sleep, dealing with the reasons behind their use of caffeine, instead of depending on a stimulant, or drug, to give them a short term solution, or “pick me up”. 















Literature Cited


Mindell, J., Meltzer, L., Carkadon, M., Chervin, R., et al. (2009) Developmental aspects of sleep hygiene: Finding from the 2004 National Sleep Foundation “Sleep in America Poll”.  Sleep Medicine, 10(7), 771-779. 


Paterson, L., Wilson S., Nutt, D., Hutson, P., Ivarsson, M., et al. (2009) Characterisation of the effects of caffeine on sleep in the rat: a potential model of sleep disruption.  J Psychopharmacology, 23, 475-486.


Pollack, C., Bright, D., et al. (2003) Caffeine consumption and weekly sleep patterns in US seventh-, eighth-, and ninth-graders.  Pediatrics, 111(1), 42-46. 




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