Napping Twice Daily: Healthy Habit Or Sleep Disorder?

Is it healthy to sleep twice a day? This question has sparked curiosity and debate among sleep researchers and the general public alike. The concept of biphasic or segmented sleep involves two sleep periods: a longer nighttime sleep and a shorter daytime nap. While some argue that this approach may suit our body clocks better than a single eight-hour sleep, others caution against disrupting the traditional monophasic sleep pattern. So, what does the research say, and is it time to embrace the siesta?

Segmented sleep may be the way to go in today's fast-paced world

Segmented sleep, or biphasic sleep, is a sleep pattern that involves two sleep periods per day. This could be a longer nighttime sleep combined with a shorter daytime nap, or two equally long sleeps at night.

The idea of segmented sleep is not new. In pre-industrial times, it was common for people to wake up for a couple of hours in the middle of the night. They would spend this time praying, smoking, having sex, or visiting their neighbours before going back to sleep until morning.

There is also evidence that humans naturally followed a biphasic sleep schedule before the widespread adoption of artificial lighting. A study by the National Institute of Mental Health found that participants who were exposed to 10 hours of light per day—similar to a winter's day—slept in two chunks with a few hours of wakefulness in between.

Today, segmented sleep is practised by people across different cultures. For example, those who enjoy siestas are considered biphasic sleepers. Some people also adopt this sleep schedule to maximise their productivity, as it can increase alertness and provide greater flexibility.

However, there are some potential downsides to biphasic sleep. It may not be feasible for those with strict work schedules or family commitments. There is also a risk of sleep deprivation if the total sleep time is insufficient, which can lead to serious health problems.

Additionally, the timing of each sleep session is crucial to falling asleep quickly and staying asleep. Exposure to artificial light during the waking hours can also impact circadian rhythms, so it is recommended to keep the light dim and avoid blue light.

While segmented sleep may not be suitable for everyone, it is worth considering its potential benefits in today's fast-paced world. It can provide increased alertness and flexibility, allowing people to make the most of their time. However, it is important to ensure that the sleep schedule includes at least seven hours of sleep per 24-hour period to avoid the negative consequences of sleep deprivation.

There are mixed views on whether segmented sleep is safe

Segmented sleep involves sleeping in two shifts or two separate periods of sleep in a day. This type of sleep pattern is not new and was common in pre-industrial times when people would go to bed early in the evening and wake up a few hours later, staying awake for a couple of hours before falling back asleep until morning. In fact, a study by the National Institute of Mental Health found that people who were exposed to 10 hours of light a day, similar to a winter's day, slept in two chunks with a few hours of wakefulness in between. This is also closer to how animals sleep.

Some researchers argue that biphasic sleep is not natural but is influenced by external factors such as eating habits, social schedules, and hot afternoon temperatures. Additionally, following a biphasic sleep schedule may not be feasible for everyone due to work or family commitments. One of the main concerns with biphasic sleep is the potential for sleep deprivation, which can increase the risk of serious health problems.

On the other hand, segmented sleep can provide benefits such as increased alertness, improved time management, and greater flexibility. A 2016 study from the Centre for Sleep Research at the University of South Australia found that having two separate sleep periods provided "two periods of increased activity, creativity and alertness across the day". Additionally, midday napping has been consistently linked to improved cognitive performance.

While there are potential benefits to segmented sleep, there has not been extensive research on the effects of shift sleeping on health. As a result, it is recommended to avoid segmented sleep unless there is a specific reason for adopting this sleep pattern.

Biphasic sleep may be more common than you think

Biphasic sleep, or sleeping in two segments per day, may be more common than you think. While many people sleep for seven or eight hours straight, some people still adopt biphasic sleep in contemporary settings. This includes people who enjoy siestas, which are considered biphasic sleepers. Additionally, many animals are biphasic sleepers, including birds, insects, and mammals.

The practice of biphasic sleep is not new and has been observed in pre-industrial times and various cultures. In pre-industrial times, it was normal for people to get up for a couple of hours in the middle of the night, according to historian Roger Ekirch. People spent this time praying, smoking, having sex, or visiting their neighbours before going back to sleep until morning.

The original biphasic sleep schedule, which split nighttime sleep into two segments with a waking hour around midnight, was common around the world. This type of sleep schedule was observed even in cultures near the equator, where residents' circadian rhythms are not affected by changing seasons.

In monophasic sleep, which is the dominant sleep pattern today, a person attains all their sleep in one block of time, typically at night. Researchers hypothesize that monophasic sleep became prevalent during the industrial era when artificial lighting enabled people to stay up past sunset.

However, our current monophasic sleep patterns might come with disadvantages. Exposure to more artificial light, especially at night, can decrease melatonin levels and negatively impact our sleep. Additionally, some people have natural sleep patterns that resemble biphasic or polyphasic sleep.

There are potential benefits to biphasic sleep. Midday napping has been consistently linked to improved cognitive performance, and shorter naps have been shown to reduce sleepiness and improve cognitive function. Biphasic sleep can also increase alertness, improve time management, and provide greater flexibility in one's daily routine.

However, there are also potential downsides to biphasic sleep. One concern is the potential for sleep deprivation, as chronic sleep deprivation can increase the risk for serious health problems. Additionally, following a biphasic sleep schedule may not be feasible for everyone due to work or family commitments.

While biphasic sleep may have its advantages and disadvantages, it is important to note that sleep is essential for overall well-being. If you are considering changing your sleep schedule, it is beneficial to consult with your doctor first.

Sleep deprivation can have serious health consequences

While sleeping twice a day, or segmented sleep, may be a trendy idea, it is not necessarily a healthy one. The human body needs sleep to function, and a lack of sleep can have serious health consequences.

Firstly, sleep deprivation affects your central nervous system. Sleep is necessary to keep your central nervous system functioning properly, but chronic insomnia can disrupt how your body sends and processes information. Sleep deprivation leaves your brain exhausted, making it difficult to concentrate or learn new things. You may also experience microsleep during the day, which can be dangerous if you are driving or operating heavy machinery.

Secondly, sleep plays a critical role in maintaining your physical health. Sleep deprivation can cause weight gain and obesity by affecting the levels of hormones that control feelings of hunger and fullness. It can also lead to diabetes by disrupting the body's method for processing glucose and reducing insulin production. Sleep deficiency is also a risk factor for cardiovascular disease, with studies linking insomnia to an increased risk of heart attack and stroke.

Thirdly, sleep is essential for maintaining good mental health. Sleep loss and disorders can contribute to symptoms of depression and anxiety. Sleep cycles and mood regulation are regulated by the hormone melatonin, and people with insomnia often have lower levels of melatonin. Sleep deprivation can also lead to faulty brain function, including memory loss and a decreased ability to regulate emotions and make decisions.

Finally, sleep is crucial for a healthy immune system. Sleep deprivation prevents your immune system from building up its defences, making you more susceptible to illnesses and increasing the time it takes to recover from them.

In conclusion, while segmented sleep may work for some individuals, it is important to prioritize getting an adequate amount of uninterrupted sleep to minimize the risk of these serious health consequences.

The biphasic sleep schedule may not be feasible for everyone

The biphasic sleep schedule, which involves two sleep periods, a longer nighttime sleep and a shorter daytime nap, may not be feasible for everyone. While some people may find that this sleep pattern comes naturally to them and works well, others may struggle to adapt to it due to external factors such as work schedules or family commitments.

For those with strict work schedules, taking a nap during the workday may not be possible or well-received by employers. This is especially true if the nap needs to be a few hours long to align with the biphasic sleep schedule. In addition, those with caregiving responsibilities may find it challenging to adhere to a strict biphasic sleep schedule as their sleep times may be interrupted or unpredictable.

Furthermore, there is a potential risk of sleep deprivation with the biphasic sleep schedule. If the daytime nap is too close to bedtime or if the nighttime sleep is interrupted, individuals may not get the recommended seven hours of sleep per 24-hour period. Chronic sleep deprivation can increase the risk of serious health problems, including heart disease, kidney disease, diabetes, stroke, high blood pressure, obesity, and depression.

Changing one's sleep pattern can also negatively impact the body's energy levels and disrupt the circadian rhythm and biological clock. This disruption can have consequences for overall health and well-being. Therefore, it is essential to consider individual circumstances and seek professional advice before making significant changes to one's sleep schedule.

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