Sleeping For Two Days: Is It Possible?

Sleep is an essential part of a healthy lifestyle, alongside diet and exercise. However, in today's fast-paced world, many people do not get the recommended seven to nine hours of sleep per night, leading to a build-up of sleep debt. While it may seem tempting to try and make up for lost sleep by sleeping for longer on the weekends, this can actually throw off your internal body clock and lead to insomnia. So, what happens if you don't sleep for a prolonged period, and is it possible to sleep for two days straight?

The impact of sleep deprivation on health

Sleep is a vital physiological process that allows the body and brain to rest, recover, and perform essential functions, including memory consolidation, emotional regulation, immune function, and general health maintenance. Sleep deprivation can have far-reaching and surprising effects on health and can impair everyday functioning.

Impact on Brain Function

Sleep deprivation can affect the brain in several ways. It can impair memory, concentration, and the ability to process information. Even short-term sleep deprivation can disrupt these functions. Sleep plays a crucial role in memory formation and consolidation, and a lack of sleep can lead to cognitive decline and a higher risk of dementia.

Additionally, sleep is necessary for the brain to flush out toxic waste products that build up during the day. The accumulation of these toxic proteins is linked to the development of Alzheimer's Disease.

Sleep deprivation can also negatively impact emotional regulation, leading to mood swings, irritability, and other mental health issues. It can compromise decision-making, creativity, and judgement, and increase the risk of accidents. In severe cases, long-term sleep deprivation can even induce hallucinations.

Impact on Physical Health

Sleep deprivation can have a detrimental effect on physical health, increasing the risk of various chronic conditions. It is linked to a higher chance of developing obesity, type 2 diabetes, hypertension, and some cancers, such as colorectal cancer. It can also weaken the immune system, making individuals more susceptible to infections and prolonging recovery from illnesses.

Sleep also plays a vital role in maintaining cardiovascular health. Sleep deprivation can disrupt processes that keep the heart and blood vessels healthy, including regulating blood sugar, blood pressure, and inflammation levels. As a result, individuals who don't get enough sleep are more likely to develop cardiovascular disease, with insomnia being associated with an increased risk of heart attack and stroke.

Impact on Everyday Functioning

Sleep deprivation can have noticeable effects on everyday functioning. It can lead to poor concentration, reduced reaction times, altered mood, and fatigue. In children, it can negatively impact behaviour and school performance.

Treatment and Prevention

The most basic treatment for sleep deprivation is to get adequate sleep, typically 7 to 9 hours each night for adults. However, this can be challenging due to various lifestyle, work, and environmental factors. To improve sleep quality and duration, it is recommended to maintain a consistent sleep schedule, create a comfortable sleeping environment, limit caffeine and alcohol intake, and avoid electronic devices before bed.

If sleep deprivation persists, seeking help from a healthcare professional is advised, as it could be a sign of an underlying sleep disorder.

Sleep debt and recovery

Sleep debt, or sleep deficit, occurs when a person gets less than seven hours of sleep per night. This can quickly add up when you consider the many activities that can cause sleep loss, such as work, commuting, socialising, relaxing, and watching TV.

The effects of sleep debt are cumulative, meaning that going to sleep 30 to 60 minutes later than usual for a few days can quickly result in a significant sleep debt. As sleep debt builds, brain and body functioning deteriorate, and the risk of diabetes, hypertension, heart disease, and stroke increases. Sleep debt also negatively impacts immune function, cognitive function, and can cause weight gain.

If you have accumulated sleep debt, allow extra time for sleep by going to bed early. When you are sleep-deprived, you sleep more deeply, so you do not need to "pay back" hour for hour. However, if you have been sleep-deprived for many days, it might take several nights of good-quality sleep to recover.

• Stay consistent: Maintain a set sleep schedule by setting your bedtime and morning alarm at the same times every day, even on weekends. This is important for resyncing your circadian rhythms.
• Keep a diary: A sleep diary can help you track your sleep habits and identify patterns or practices that are affecting your sleep.
• Try an afternoon nap: While napping is not a replacement for lost sleep, a short power nap can refresh the body and brain.
• Give it time: Remember that it can take several days to recover from sleep debt. Increase your sleep time slowly, by 15 to 30 minutes at a time, until you reach the optimal amount of sleep for your body.
• Talk to your doctor: If sleep debt is interfering with your daytime activities or if you are struggling to recover, speak with your doctor. They can help determine if you have an underlying sleep disorder and offer personalised tips for improving your sleep.

Sleep cycles and stages

Sleep is not uniform. Instead, over the course of the night, your total sleep is made up of several rounds of the sleep cycle, which is composed of four individual stages. In a typical night, a person goes through four to six sleep cycles lasting about 90 minutes each. The first sleep cycle is often the shortest, ranging from 70 to 100 minutes, while later cycles tend to fall between 90 and 120 minutes.

The four sleep stages can be divided into two categories: rapid eye movement (REM) and non-rapid eye movement (NREM). NREM sleep is composed of three different stages. The higher the stage of NREM sleep, the harder it is to wake a person up.

Stage 1 (NREM)

Stage 1, called N1, is the lightest stage of sleep and lasts for about 1 to 5 minutes. Your brainwaves, breathing, and heart rate all begin to slow, and your muscles relax. During N1 sleep, the body has not fully relaxed, though the body and brain activities start to slow with periods of brief movements. It is easy to wake someone up during this sleep stage, but if a person is not disturbed, they can move quickly into stage 2.

Stage 2 (NREM)

In stage 2, which is called N2, your body temperature drops while your heart rate and breathing continue to slow. Stage 2 lasts for about 10 to 25 minutes in your first sleep cycle and gets longer with each additional cycle. During this stage, your brain waves show a new pattern and eye movement stops. On the whole, brain activity slows, but there are short bursts of activity that actually help resist being woken up by external stimuli.

Stage 3 (NREM)

Stage 3, also called N3 or deep sleep, is when your body repairs itself and strengthens your immune system. Even loud noises may not wake you from this stage of sleep. The brain activity during this period has an identifiable pattern of what are known as delta waves. For this reason, stage 3 may also be called delta sleep or slow-wave sleep (SWS). Experts believe that this stage is critical to restorative sleep, allowing for bodily recovery and growth. It may also bolster the immune system and other key bodily processes.

Stage 4 (REM)

REM sleep is the cycle where you’re most likely to dream and is characterized by paralyzed muscles and quickly moving eyes. It usually begins about 90 minutes after you fall asleep, and during each cycle throughout the night, it gets longer. During REM sleep, brain activity picks up, nearing levels seen when you are awake. At the same time, the body experiences atonia, which is a temporary paralysis of the muscles, with two exceptions: the eyes and the muscles that control breathing. Even though the eyes are closed, they can be seen moving quickly, which is how this stage gets its name.

Sleep pressure and sleep hygiene

Sleep pressure is a feeling of tiredness that gets stronger the longer you stay awake. If you don't sleep, your drowsiness will continue to worsen until you can finally rest. While you're asleep, your body cycles through four stages of sleep roughly every 90 minutes. On a normal night, you get 4 to 6 of these cycles.

The four sleep stages can be divided into two categories: rapid eye movement (REM) and non-rapid eye movement (NREM). NREM makes up about 75 to 80% of your sleep.

Stage 1 (NREM) is the lightest stage of sleep, lasting about 1 to 5 minutes. Your brainwaves, breathing, and heart rate all begin to slow, and your muscles relax. In stage 2 (NREM), your body temperature drops further while your heart rate and breathing continue to slow. This stage lasts about 25 minutes in the first sleep cycle and lengthens with each additional cycle.

Stage 3 (NREM) is deep sleep, when your body repairs itself and strengthens your immune system. Even loud noises are unlikely to wake you. Stage 4 (REM) sleep is when you're most likely to dream. It's characterised by paralysed muscles and rapidly moving eyes, beginning about 90 minutes after falling asleep.

If you're not getting enough sleep, you're likely to experience impaired reaction time, and your judgment and cognitive abilities will be impaired. Regularly getting less than 6 hours of sleep increases your risk of falling asleep at the wheel.

'Sleep hygiene' refers to healthy habits, behaviours, and environmental factors that can be adjusted to help you get a good night's sleep. Good sleep hygiene is important because of how crucial good sleep is for your mental and physical health, as well as your overall quality of life. Your behaviours during the day—not just before bed—can affect how well you sleep.

• Keep a consistent sleep schedule, even on weekends.
• Create a relaxing bedtime routine, and stick to it.
• Turn off electronic devices before you sleep.
• Exercise regularly, but not too close to bedtime.
• Limit your caffeine intake, especially in the afternoon or evening.
• Make your sleep environment comfortable and conducive to sleep.
• Use your bed only for sleep and sex.
• Go to bed only when you're tired.
• Limit napping during the day.
• Manage stress before bedtime.
• Avoid large meals, alcohol, and nicotine before bed.
• Manage your light exposure, getting natural light during the day and reducing blue light exposure in the evening.

Segmented sleep

The idea of segmented sleep is not new. In pre-industrial times, it was common for people to get up for a couple of hours in the middle of the night, spending this time praying, smoking, having sex, or visiting their neighbours. Historian Roger Ekirch, author of 'At Day's Close: Night in Times Past', argues that segmented sleep was the norm in Western civilisation before the Industrial Revolution.

In the modern world, segmented sleep is often a necessity for shift workers, new parents, and students during exam periods. However, it is not considered a healthy or sustainable practice. Our bodies rely on deep sleep for restoration, physical recovery, memory consolidation, and strengthening the immune system. By sleeping multiple times during the day, one may never build up enough deep sleep to achieve these benefits.

There is also the issue of timing. Our bodies follow a circadian rhythm, a 24-hour cycle that influences when we are alert, sleepy, and hungry. Trying to sleep during the day goes against these cues, and deep sleep may be harder to attain.

A study published in the journal Scientific Reports in 2017 found that university students who followed irregular, segmented sleep schedules had disruptions to their circadian rhythms, equivalent to travelling west by two to three time zones. They also had lower grades compared to their peers who slept a steady single block of sleep, even when both sets of students slept the same number of hours.

If one must follow a segmented sleep schedule, experts recommend aiming for close to eight hours of sleep in a 24-hour period. It is also important to stick to a consistent schedule, as switching back and forth can scramble your circadian rhythm. Additionally, try to get the majority of your sleep at night when your body is naturally craving rest, and avoid napping after 7 pm to maintain your sleep drive.

Frequently asked questions