Daytime Sleep: Friend Or Foe?

Sleep is a vital part of our daily routine, with the average adult requiring 7-9 hours of sleep per night. However, for those who work night shifts or have jet lag, sleeping during the day is unavoidable. So, what effect does sleeping through the day have on the body?

Daytime sleep can disrupt the body's natural circadian rhythm, which is controlled by a biological clock located in the brain. This clock responds to light cues, triggering the production of melatonin at night, and switching it off when it senses light. As a result, sleeping during the day can impact the body's melatonin production, leading to potential health issues.

In addition, daytime sleep can affect the quality of sleep, reducing the time spent in deeper, more restorative sleep stages. This can result in excessive daytime sleepiness, impacting overall health and well-being.

Furthermore, sleeping during the day can be challenging due to environmental factors such as light and noise, which can interfere with sleep cycles and cause fragmented sleep.

Overall, sleeping during the day can have various effects on the body, including potential disruptions to the circadian rhythm, reduced sleep quality, and increased sleepiness. Understanding these effects is crucial for managing daytime sleep and maintaining overall health.

Increased risk of chronic diseases

Oversleeping is associated with an increased risk of chronic diseases, including diabetes, obesity, heart disease, and even death.

Sleeping too much can also negatively impact your immune system, mental health, and heart health. Research has shown that sleeping too long or not enough each night can increase the risk of diabetes. One study found that people who slept for nine or ten hours every night were 21% more likely to become obese over a six-year period than those who slept between seven and eight hours. This association remained the same even when factors like food intake and exercise were taken into account.

Another study involving nearly 72,000 women found that those who slept nine to eleven hours per night were 38% more likely to have coronary heart disease than those sleeping eight hours. While researchers have not yet determined the exact reason for this connection, they speculate that depression and low socioeconomic status, which are associated with longer sleep, could be contributing factors.

Additionally, a lack of sleep can also have adverse effects on health. Not getting enough sleep is linked to symptoms of depression, seizures, high blood pressure, migraines, compromised immunity, and even a prediabetic state in healthy individuals.

While the causes of oversleeping can vary, it is essential to maintain healthy sleep habits and consult a healthcare professional if you have concerns about your sleep patterns.

Disruption of the body's internal clock

Circadian rhythms, or our body's internal clock, are controlled by a biological clock located in the brain. One of its key functions is to respond to light cues, increasing the production of the hormone melatonin at night, and switching it off when it senses light. People with total blindness often struggle with sleep because they are unable to detect and respond to these light cues.

Our body craves sleep, much like it craves food. Throughout the day, our desire for sleep builds, and when it reaches a certain point, we need to sleep. However, unlike hunger, our body can force us to sleep when we are exhausted, even if we are in a meeting or behind the wheel of a car. This is known as microsleep, and our body can engage in microsleep episodes of one or two seconds even when our eyes are open.

Napping for more than 30 minutes during the day can disrupt our night's sleep by decreasing our body's sleep drive. Our sleep drive is our body's need for sleep. For people who maintain a traditional sleep-wake schedule, napping in the early afternoon (between 1 p.m. and 3 p.m.) is optimal, as this is when most people experience a natural decline in energy and alertness, known as the "post-lunch dip" or "afternoon slump". Napping during this time can boost energy levels, increase alertness, improve mood, enhance memory and cognitive ability, and improve physical ability.

In general, experts recommend limiting your nap to at least eight hours before bedtime to avoid nighttime sleep problems. Napping for 30 minutes or less is ideal, as it allows the body to get some light sleep without entering deep sleep. If you wake up during deep sleep, you may find yourself feeling groggier than before you napped. In some cases, napping for 90 minutes can also be beneficial, as it allows the body to cycle through the stages of sleep and avoids disrupting deep sleep.

If you find yourself frequently napping during the day, you may not be getting the recommended amount of sleep at night. If you still need naps despite getting adequate sleep, talk to your doctor to assess your sleep quality and rule out any potential sleep disorders.

Negative impact on mental health

Sleeping through the day can have a detrimental effect on mental health, and this is supported by extensive research. Firstly, it is important to understand the bidirectional relationship between sleep and mental health. Sleep disturbances can both be a symptom and a cause of mental health issues. Therefore, sleeping through the day can be both a consequence and a trigger for mental health problems.

Brain Function and Emotional Regulation

Sleep is crucial for optimal brain function, including concentration, memory, and emotional regulation. A lack of sleep can lead to "brain fog," making it challenging to focus, recall information, and find the right words. It also impairs decision-making abilities and productivity.

Mood Changes and Irritability

Not getting enough sleep or sleeping at unusual times can cause mood changes, including increased irritability and anxiety. Research has also linked sleep deprivation to heightened levels of anger and aggression. This is due to the brain's inability to suppress the reactivity of the amygdala, the emotional center of the brain. As a result, individuals may experience difficulty controlling their emotions and feel more irritable.

Impulsive Behaviour and Emotional Outbursts

Lack of sleep can lead to impulsive behavior, hyperactivity, and emotional outbursts. Social interactions may become more challenging, and individuals may act erratically, exhibiting a short temper.

Stress and Minor Hassles

Poor sleep quality can make it harder to cope with stress, and daily hassles can become significant sources of frustration. The very thought of not getting enough sleep can become a stressor itself, creating a cycle of worry and sleep disturbances.

Risk of Psychiatric Disorders

Sleeping through the day can increase the risk of developing various psychiatric disorders. Research has found links between sleep disturbances and depression, anxiety, bipolar disorder, and even suicidal ideation. Sleep problems can trigger the onset of these conditions or exacerbate existing symptoms.

Psychotic Symptoms

Severe sleep deprivation has been associated with the development of temporary psychotic symptoms. Studies have shown that participants who went without sleep for extended periods experienced hallucinations, delusions, and other perceptual changes.

Increased Risk of Mental Distress

Inadequate sleep is strongly correlated with frequent mental distress. Those who get less sleep are more likely to experience mental health issues and report feeling unwell mentally.

Treatment Considerations

Addressing sleep problems is crucial for managing mental health. Cognitive Behavioral Therapy for Insomnia (CBT-I) is a recommended treatment option, focusing on changing sleep-related behaviors and thought patterns. Other interventions include sleep studies, over-the-counter sleep aids, and prescription sleep medication for short periods.

In summary, sleeping through the day can have a detrimental effect on mental health, impacting brain function, emotional regulation, mood, stress levels, and the risk of developing psychiatric disorders. Addressing sleep problems is an essential aspect of maintaining and improving mental well-being.

Weight gain

Sleep is just as important as diet and exercise when it comes to weight management. Lack of sleep can lead to weight gain in several ways. Firstly, it lowers your metabolism, making it harder to burn calories. Secondly, it increases the production of the hunger hormone, ghrelin, and decreases the production of the satiety hormone, leptin, leading to increased feelings of hunger. Thirdly, sleep deprivation affects the decision-making areas of the brain, making it harder to resist tempting, unhealthy foods. Poor sleep can also lead to increased levels of cortisol, a stress hormone that can increase appetite. Finally, being tired can reduce your motivation to exercise and make you more likely to be sedentary, further contributing to weight gain.

Several studies have found a link between sleep deprivation and weight gain. One study showed that participants ate an extra 300 calories per day when sleep-deprived, with most of the extra intake coming from fats. Another study of over 170 participants found that a single night of inadequate sleep led to an extra 385 calories being consumed the next day. A clinical trial also found that sleep-deprived participants ate significantly more calories and had a preference for fatty foods.

The effects of sleep deprivation on weight gain can be seen in both adults and children. In adults, sleeping fewer than 6-7 hours per night has been linked to a higher body mass index (BMI) and weight gain. One analysis found a 41% increased obesity risk among adults who slept fewer than 7 hours. In children, sleep loss increases the risk of becoming overweight or obese and can lead to the same hormonal changes that lead to weight gain in adults.

Breaking the cycle of sleep loss and weight gain can be challenging. However, improving sleep quality and duration can help to reverse the effects of sleep deprivation on weight. Establishing healthy sleep habits, such as maintaining a regular sleep schedule and avoiding heavy meals before bed, can support weight loss efforts.

Eye strain

Spending long periods of time staring at screens such as computers, smartphones, or televisions without adequate rest can cause eye strain, which in turn can lead to discomfort, headaches, and overall eye fatigue.

The blue light emitted by electronic devices is particularly harmful to the eyes, and constant exposure to it over time could damage retinal cells and cause vision problems such as age-related macular degeneration, cataracts, eye cancer, and growths on the clear covering over the white part of the eye. Blue light exposure before bedtime can also disrupt sleep patterns, as it affects the body's creation of melatonin.

According to The Vision Council, more than 60% of adults spend at least five hours a day on digital devices, and many of them experience digital eye strain. Studies have shown that people blink less when looking at screens, which can lead to dry, burning eyes.

To reduce eye strain, it is recommended to follow the 20-20-20 rule: every 20 minutes, take a 20-second break from looking at your screen and focus on something that is 20 feet away. Other tips include adjusting your screen position and lighting, using blue light filters, and remembering to blink more often.

In addition to eye strain, lack of sleep can cause other eye-related issues such as dry eyes, bloodshot or red eyes, swollen eyes or eyelids, sensitivity to light, and eye twitches (myokymia). Chronic sleep deprivation has also been linked to an increased risk of eye conditions such as glaucoma and age-related macular degeneration.

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