Excessive Daytime Sleepiness -- Why Do You Feel Sleepy in the Afternoon

Daytime sleepiness is a known condition that is experienced by the global population.
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The medical field has long established that each individual human body obeys by a set of fundamental principles that denotes the primary functions and basic capabilities. Every individual can benefit from eating a healthy range of food while they are equally susceptible to infections, bacteria, and viruses. More importantly, the underlying basis of all scientific discoveries has remained consistent throughout the years. The global population has come to realize that the body’s underlying mechanism is a complicated set up of the cause-and-effect system. Everything that the body comes into contact with results in a reaction. For instance, people who are allergic to nuts will suffer from its consequences almost instantaneously. Individuals who exercise regularly will get to reap the benefits of having a better physique. Although the effect of each action is subject to the time factor, the chain reaction that follows is undeniable.


The influence of each element varies from one individual to another as other factors can potentially alter the effect. People living at opposite ends of the world are exposed to different types of illnesses and diseases while individuals with different backgrounds have drastically distinct medical risks as well. Other factors that play an active part in this area include age groups, genders, racial background, and lifestyle habits. Interestingly, there are several conditions that have escaped these restrictions and are known to affect the population at large. A unique example can be seen in the phenomenon of daytime sleepiness. It has been widely discussed within social circles and have garnered much attention in the medical field. The trendy population has even nicknamed this effect as Afternoon Fatigue or The 2:30 Feeling. Having seen its exponential rise to notoriety, scientists have now provided credible evidence to support this seemingly innocuous condition. Based on scientific experiments and investigative studies, they were able to attribute several causes that can increase the risk of daytime sleepiness.

Causes of Daytime Sleepiness

  • Prior Brain Injuries

The association between brain injuries and daytime sleepiness is arguably one of the most disturbing discoveries made by scientists. In 2007, the Department of Neurology at the University of Washington set out to evaluate the relationship between both factors. A total of 514 participants were enrolled into this study, each with a history of brain injuries. The study lasted a total of 13 months where medical evaluations of each subject were collected at regular intervals.

Based on the collated results, the scientists discovered that excessive sleepiness that extends into daytime is a common effect seen in patients with brain injuries. It was also determined that more severe traumatic brain injuries lead to greater symptoms of sleepiness. However, more than 75 percent of the patients gradually improve from their condition after a one-year period while the remaining quarter percentile continued to exhibit excessive sleepiness.

A separate experiment conducted by the University Hospital Zurich in Switzerland yielded similar findings. Only 36 patients were eligible for this study and each subject exhibited an increased need of sleep by up to 3 hours per day as compared to the control participants. On the average, patients who suffered from traumatic brain injuries required 10.8 hours of sleep whereas normal subjects only needed 7.3 hours. The scientists also deduced that patients tend to underestimate their sleep requirement which consequently contributes to daytime sleepiness as well.

  • Inadequate Sleep Cycle

Not surprisingly, the prevalence of daytime sleepiness starts from the night. An inadequate sleep cycle is a predominant cause of this condition in the general population. A satisfied sleep experience can be disrupted by many factors, such as insufficient hours, distractions during bed times, or an irregular lifestyle.

Sleep specialists have recommended several principles that can aid in achieving a fulfilling sleep cycle. For example, individuals are strongly advised to keep any distractions out of their beds. Most of the people are known to sleep with their mobile phones within reach but scientists have shown that this habit can potentially harm a sleep cycle.

On the other hand, establishing a regular sleep pattern and ritual is an effective way to help the body engage in adequate rest. This can be done by setting a consistent bedtime and waking up time. Taking naps late in the afternoon should also be avoided while regular exercises can also aid in improving sleep experience.

  • Arthritis

Based on the accounts of past and present patients, the onset of arthritis joint pain is always accompanied by daytime sleepiness. Such a relationship is primarily due to the patient’s inability to indulge in an adequate sleep cycle during the night and suffers the consequences the following day. This theory is credited by medical professionals from the Sleep Disorders and Research Center at the Henry Ford Hospital where 16 arthritis patients and 16 healthy control subjects took part in an 8-hour nocturnal sleep study and completed a Multiple Sleep Latency Test the following day. The results conclusively showed that patients with arthritis have lesser total sleep time and an increased daytime sleepiness when compared to the healthy subjects.

  • Natural Body Rhythm

Some cultures believe that daytime sleepiness is the body’s natural rhythm. Countries such as Spain and Japan recognizes this by incorporating nap times into their daily working hours. Big corporations, such as The Huffington Post and Google, have also been lauded for installing napping pods for their employees to recharge in the afternoon. The American Dietetic Association explains that this natural body reaction might be due to the early working hours and late nights that the modern society has become accustomed to.

  • Result of Dietary Plans

According to various medical literature, the human body used to convert fats into fuel for energy but procedure has evolved in recent times as the body has adapted to sugar and glucose as its primary source of energy instead. Consequently, the body suffers from low glucose levels in the afternoon and individuals experience a significant decrease in energy levels.

Naturally, this leads to the onset of daytime sleepiness. To correct this chain reaction, health experts advise consuming large amounts of healthy fats that can be found in foods such as raw nuts, avocados, and pasture-finished meats. In this way, the individuals are supplied with a constant flow of energy and eliminates the prevalence of daytime sleepiness.


Daytime sleepiness is a known condition that is experienced by the global population. Working adults are known to be less productive after lunch hours while students tend to snooze during afternoon classes. Investigative studies done by medical professionals have yielded several causes of this phenomenon and provided viable measures to eliminate its prevalence. For instance, changes in dietary plans and the implementation of a regular sleep schedule can effectively help individuals eliminate daytime sleepiness from their daily routine. ON the other hand, scientists have also discovered that patients with a history of traumatic brain injuries or arthritis are at an increased risk of daytime sleepiness as well. Nonetheless, the influence of this condition can be alleviated by prescribing specific medications.