We all enjoy a good cup of joe in the morning to help us start our busy work days and feel more alert. The caffeine found in coffee is what gives us a boost in energy and focus, helping us power through the day. Many people drink coffee or consume other beverages and forms of caffeine in order to stay focused and productive throughout the day. However, although caffeine is beneficial for a quick energy boost, it cannot replace a proper night’s sleep. When you’re short on sleep caffeine may make you feel energized and focused but in reality your cognitive abilities will be impaired. Although caffeine has been shown to provide some aid to our brain’s ability to focus, it simply cannot match what natural sleep does for our brain’s health.
In a study published in the Journal of Experimental Psychology: Learning, Memory, & Cognition, a group of participants subjected to a night of sleep deprivation was asked to complete a reaction time test as well as a more complex “place-keeping” test, which required the completion of a series of tasks in a specific order without skipping or repeating any steps. The researchers noted that caffeine did help in some instances, “We found that sleep deprivation impaired performance on both types of tasks and that having caffeine helped people successfully achieve the easier task. However, it had little effect on performance on the place-keeping tasks for most participants,” said Kimberly Fenn, PhD, an associate professor in the department of psychology at Michigan State University. According the Dr. Fenn there is a simple takeaway from the study, “Caffeine may be able to help you stay awake and pay attention to a task, but it does not help to prevent errors,” she said. “We are interested in procedural errors because they can be quite dangerous. For example, many medical professionals, such as surgeons, need to work long hours throughout the night. I think the best way to conceptualize this is that one would not want to attempt any task that has consequences such as driving or operating heavy machinery while sleep deprived.”
The control group for the study slept normally at home while the experimental group was kept awake in a lab overnight. They then consumed either a placebo or 200 milligrams of caffeine, approximately the amount in one to two cups of coffee (depending on the size of the cup and strength of the coffee). The findings of the study support the theory that sleep deprivation impairs our “vigilant attention”, reducing our ability to complete cognitive tasks that require attention. “Caffeine can help you get through a midday slump, but it isn’t a substitute for a good night’s rest,” said Dr. Anthony Puopolo, chief medical officer of the telemedicine company RexMD. According to Dr. Puopolo, adequate sleep is especially vital for people working in high-functioning environments who often have to work long hours, such as doctors and truck drivers. Making sure you maintain a stable work-life balance can help you manage your sleeping patterns and ensure that your brain can operate the way its supposed to.
So why does sleep have such an effect on our ability to perform cognitive tasks? You see, during deep sleep the tissues in our bodies are repaired and our brains are cleared of plaque buildup. During REM sleep, which is the deepest stage of sleep, neural connections in our brains are formed and our memories are consolidated. This allows our brains to repair themselves and also process new information that we took in throughout the day, leading to improved cognition and mental performance. Unfortunately, caffeine cannot provide this same level of restoration since it merely blocks the chemicals, such as adenosine and melatonin, that make us feel tired. Although caffeine is successful in covering up the symptom of feeling sleepy, it will not make the brain more rested and can actually harm your quality of sleep in high doses (anything over 400mg a day). Eventually, with enough regular caffeine usage our bodies develop a tolerance and require more of it to feel its stimulant effects which can end up leading to increased sleeplessness. With everything considered, caffeine can be a great supplemental form of energy but should never be used as a replacement for quality sleep. Managing things like your caffeine consumption, stress, and exercise habits can help you improve your sleep and put down that extra cup of joe!