Daytime Sleep: Is It A Silent Killer?

Sleep is essential for good health, but can too much sleep be harmful? Several studies have found a link between excessive sleep and an increased risk of early death. One study suggests that sleeping more than the recommended 7 to 8 hours a night can increase the risk of stroke, heart failure, and other cardiovascular problems. Another study found that adults who nap during the day are more likely to die from respiratory illnesses, as napping can cause inflammation in the body. However, it's important to note that these studies have limitations and do not establish a direct cause-and-effect relationship between daytime napping and increased mortality.

Napping during the day may increase the risk of premature death

A study of 16,000 British people over 15 years found that napping during the day could increase the risk of premature death by a third. However, the study also had many caveats and was deemed interesting but inconclusive.

The Study

During the study, roughly 3,000 of the 16,000 participants died. Scientists matched sleeping habits with the cause of death and also took into account the length of naps. They found that people who slept for less than an hour during the day increased their chance of death by 14%. This number rose to 32% if the nap lasted for more than an hour and was linked to the development of respiratory illnesses.

The Caveats

The study also suggested that a person who naps may already suffer from a lung disease, and that napping might help them. The chicken-egg dynamic comes into play here. The epidemiologic evidence of the association between daytime napping and mortality is also inconsistent and dependent on cultural, environmental, and demographic factors.

Other Studies

Other studies have also found that sleeping too much can lead to an increased risk of early death. A European study of 116,613 people from 21 countries found that sleeping more than the recommended 6 to 8 hours a night increased the risk of stroke, heart failure, and other cardiovascular problems, as well as death, by up to 41%. Another study of 24,671 adults found that sleeping more than 10 hours a night was linked to depression and obesity.

While napping during the day may increase the risk of premature death, more research is needed to confirm this. In the meantime, it is important to get enough sleep and maintain a healthy sleep schedule. Most adults need between 7 and 9 hours of sleep per night.

Sleeping during the day may cause respiratory illnesses

While sleeping is essential for good health, too much sleep can have adverse effects on the body. A study of 16,000 British people over 15 years found that those who slept during the day were two-and-a-half times more likely to die from respiratory illnesses than those who slept only at night. This may be because napping can cause inflammation in the body.

The study also found that sleeping for less than an hour during the day increased the chance of death by around 14%, and this number rose to 32% if the nap lasted for more than an hour. However, it is important to note that the cause of the respiratory illnesses could also be due to a pre-existing lung condition, and napping may be beneficial in this case.

Other studies have also found a link between too much sleep and an increased risk of death. A European study of over 116,000 people found that sleeping more than the recommended 6-8 hours a night increased the risk of stroke, heart failure, and other cardiovascular problems, as well as death, by up to 41%. Another study of 24,671 adults found that sleeping more than 10 hours a night was linked to depression, obesity, high blood pressure, and type 2 diabetes.

It is worth noting that the amount of sleep one needs can vary depending on age and gender. Older adults may sleep a little less, while women may sleep a little more. Additionally, the quality of sleep is also important, and sleep disorders or underlying health conditions can impact the duration and quality of sleep.

In conclusion, while sleeping during the day may not directly cause respiratory illnesses, it can increase the risk of developing these and other health conditions. Therefore, maintaining a healthy sleep schedule and consulting a healthcare provider for ongoing sleep problems is essential.

Sleeping too much can increase the risk of cardiovascular problems

Oversleeping has been linked to a host of medical problems, including cardiovascular disease, coronary heart disease, and an increased risk of death.

A study published in the Journal of the American Heart Association found that every extra hour of sleep over the recommended 7 to 8 hours increases your risk of dying sooner than expected. Those who sleep for 10 hours a night are 30% more likely to die young than those who sleep for eight hours. The study also linked oversleeping to a 56% increased risk of death from stroke and a 49% increased risk of death from cardiovascular disease.

While the exact cause and effect relationship is unknown, it is speculated that underlying medical conditions, such as heart disease, may be the reason for the observed negative health effects of oversleeping. For example, people of lower socioeconomic status may have less access to healthcare and, therefore, more undiagnosed illnesses that can cause oversleeping. Additionally, conditions such as sleep apnea, restless leg syndrome, and bruxism can disrupt sleep quality and lead to excessive sleepiness during the day.

If you regularly sleep more than 8 or 9 hours per night and feel rested, it might be a sign of a sleep disorder or an underlying medical condition. It is recommended to consult with a healthcare professional to discuss potential causes and treatment options, which may include a sleep study to rule out sleep disorders.

Lack of sleep can cause hallucinations

Sleep deprivation can cause hallucinations—when you see or hear things that aren't there. It can also cause delusional thinking. It is caused by severe sleep deprivation that continues for a long time.

About 80% of people will hallucinate if they've been severely sleep-deprived. "Severe" means getting only a few hours of sleep over one night or going several days without sleep. Most of these incidents involve visual hallucinations.

The effects of sleep deprivation can be cumulative, so chronically getting too few hours of rest per night can also lead to hallucinations.

In a study of sleep deprivation, all studies except one reported perceptual changes, including visual distortions, illusions, somatosensory changes, and, in some cases, frank hallucinations. The visual modality was the most consistently affected (in 90% of the studies), followed by the somatosensory (52%) and auditory (33%) modalities.

Symptoms of sleep deprivation can include:

• Perceptual distortions and hallucinations
• Mood changes (76%), which include aggression, anger, hostility, apathy, anxiety, and depression
• Disordered thoughts, confusion, and bizarre behaviour (66%), with confusion, difficulties with attention and concentration, fragmented thinking, and nonsensical speech
• Dissociation and depersonalisation (52%), with feelings of being separated from others and estrangement
• Delusions (42%)
• Distortions in the sense of time (20%)

Psychotic symptoms develop with increasing time awake, from simple visual/somatosensory misperceptions to hallucinations and delusions, ending in a condition resembling acute psychosis.

These experiences are likely to resolve after a period of sleep, although more information is required to identify factors that can contribute to the prevention of persistent symptoms.

Lack of sleep can cause accidents

Sleep deprivation can have serious consequences in the workplace, increasing the likelihood of accidents that can result in injury or even death. It is a significant safety issue in many industries, particularly those where employees are responsible for the lives of others, such as pilots, truck drivers, shift workers, and medical residents.

Several infamous accidents and disasters have been directly or indirectly caused by excessive sleepiness or sleep deprivation. Here are some examples:

Three Mile Island Nuclear Plant Incident (1979)

The worst commercial nuclear plant incident in US history occurred when shift workers, who had been working between 4 a.m. and 6 a.m., failed to recognize a serious change that nearly resulted in the meltdown of the nuclear reactor. Sleep loss directly contributed to poor judgment.

Exxon Valdez Oil Spill (1989)

The Exxon Valdez oil tanker struck Bligh Reef, releasing 10.8 million gallons of crude oil. The crew had been working round-the-clock and had very little sleep in the prior 16 hours. None of them could legally take a bridge watch when the accident occurred due to their sleep deprivation.

American Airlines Flight 1420 Crash (1999)

The National Transportation Safety Board (NTSB) cited "impaired performance resulting from fatigue" as a contributing factor in the crash of American Airlines Flight 1420, which resulted in the death of the captain and 10 passengers, with over 100 injuries. Both the captain and first officer had been awake and working for over 16 hours before the accident.

Metro-North Train Crash (2013)

In this incident, the train conductor failed to stop the train due to fatigue from undiagnosed severe obstructive sleep apnea (OSA). The NTSB report mentioned that the conductor had multiple OSA risk factors, including obesity, male gender, snoring, complaints of fatigue, and excessive daytime sleepiness.

Hoboken Train Crash (2016)

The NTSB attributed the probable cause of the Hoboken train crash, which resulted in 1 fatality and 114 injuries, to the conductor's failure to apply the brakes due to fatigue from undiagnosed OSA.

These examples illustrate the severe consequences that can result from lack of sleep. Sleep deprivation degrades cognitive processing, slows reaction time, impairs decision-making, and increases the likelihood of misjudgments and unwise risks. It is crucial to prioritize healthy sleep habits and address sleep disorders to prevent accidents and ensure safety in the workplace and beyond.

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