Although sleep is primarily a nocturnal practice, we all occasionally nap during the day. In some places napping is often cultural, such as in Mediterranean countries (eg Italy, Greece and Spain), where napping or siesta is a common habit, or in eastern countries (such as China) where napping is common as result of the high workload.
Despite being something commonplace, there is a lot of discussion about the effects of naps on our health. And the truth is, there is no simple answer to that. In some cases, sleeping during the day can be very good, but in others it can be a big problem! In this blog we will discuss naps under three conditions:
1. When are they beneficial
2. When are essential
3. When should they be avoided
1. When can naps be beneficial?
Naps every day
One of the keys to quality sleep is regularity. It's really important that we sleep and always wake up at the same time, so that our brain is conditioning and learning to maintain a sleep routine. This routine is essential to avoid or fight the symptoms of insomnia. It is important that this regularity is maintained even on weekends, avoiding creating a big difference between Saturday and Sunday sleep and weekday sleep.
The same idea of regularity applies to naps. It's okay to take a nap, as long as it's done every day, as a habit (or at least most days). In this case, it is difficult to think about the harm caused by napping, as it is part of the “equation” of our circadian cycle. That is, our brain can predict and take into account the sleep period during the day to plan daytime sleep.
This is exactly what happens during siesta, which in many countries is a very common habit. In that case, it is socially acceptable for people to take a short nap after lunch. In some locations, businesses even close so that people can rest.
Nap during childhood
In the first weeks of life, newborns spend more time sleeping than awake, and it is even difficult to distinguish between nighttime and daytime sleep. During this period, it is normal for a baby to sleep up to 19 hours a day. This sleep pattern in which the child sleeps and wakes up throughout the day is called polyphasic sleep (ie, a sleep divided over several phases). It contrasts with monophasic sleep, usually seen in adults, which occurs in only one phase throughout the day. This transition from monophasic to polyphasic sleep is slow and gradual, over a period of years until sleep settles into a single nocturnal period.
Between six and nine months of age, babies establish a pattern of three naps during a day, usually one in the morning and two in the afternoon. From nine to twelve months it is common to see a pattern of two naps during the day. After twelve months, a biphasic pattern begins to establish, with the main period of sleep during the night and a single nap during the day. This pattern usually remains for a few years, until sometime between the ages of three and seven the child begins to establish his monophasic sleep, avoiding daytime naps and concentrating everything at night.
Sleep during the first months and years of life is very important because it is related to the process of brain maturation. The brain is not 100% ready at the time of delivery and the process of brain development will continue for a few years after birth. As sleep is very important for neurodevelopment, these naps during the day are essential.
Nap in old age
When we reach old age, sleep changes a lot again. In general, the elderly have a slightly shorter nighttime sleep period, and often make their sleep polyphasic again, distributing naps throughout the day. It is estimated that at least 40% of people over the age of 65 regularly take a nap.
As with children, napping in the elderly seems to be something natural, which is part of the aging process. However, it must be understood that napping should be natural and not forced. If an elderly person feels tired, sleepy and fatigued, even napping for more than 1 hour a day, he/she should see a sleep specialist for an evaluation.
2. When are naps essential?
Naps in risky situations
Sleeping in situations that involve some risk is always very dangerous. The most talked about and known case is that of sleeping at the wheel. According to data from the Brazilian Association of Traffic Medicine, 42% of traffic accidents are related to sleep. Driving is often a repetitive and monotonous activity. For a person who is already sleepy, falling asleep while driving is almost inevitable.
The same association seen with car accidents can happen with several other types of activities that involve risk. We can put on the list the operation of heavy machinery, sports practice and civil construction. In all these cases, sleepy work can lead to very dangerous accidents.
Avoid performing these functions when you are sleepy. When we are tired, sleep and lack of attention can come on suddenly. Also, don't be fooled into thinking that turning on loud music, opening car windows, or washing your face will make you more awake. The effect of this is minimal and the chance that you will get even more sleepy only increases. If you can't put off the trip or work, try napping first so that the sleep pressure will ease a little. Also, if you feel drowsy while traveling, stop the car somewhere safe and go to sleep. Your trip will take longer if you need to take a nap before or during, but it's certainly a small problem compared to the risks of napping while driving.
Nap among night workers
We live in a 24/7 society and night work is essential to our economy and well-being. However, our physiology is not designed to keep us awake at night. Whenever we turn into a sleepless night, we are giving up our health. This is an even greater danger for night workers. As much as people try to get used to working at night, our bodies are never able to fully adapt to switching from night to day and there are certainly some consequences of this.
One of the main strategies to combat the consequences of shift work is naps. In this case, both pre-shift and during-shift naps appear to be very beneficial, increasing both performance and job satisfaction. Several studies have already shown that scheduled naps improve cognitive performance and reduce the risk of accidents.
If you are a night worker, talk to your employer to ensure that you have a suitable environment for rest at night. This is important for work safety and will certainly lead to increased productivity. Also, find a sleep specialist to design a personalized activity strategy to best suit the night shift.
Imagine that you spent the entire night writing a report for your job, which was due for a meeting at 8:00 am. Or that you spent a sleepless night studying for an exam. In those cases, after the job is done, a nap can really be invigorating.
If possible, find a quiet, comfortable and quiet place and rest for a while. Nowadays there are some companies that offer special cabins for quick naps in big cities and at airports. This nap shouldn't be longer than 1 hour (ideally it should be about 30 minutes). This is because, with longer periods of sleep, one enters into a period of deep sleep (more precisely in the N3 stage of sleep). When waking someone in deep sleep, the inertia of sleep is very high, and the person is likely to wake up disoriented and even more tired than before.
These little revitalizing naps (also called power naps) are very effective when taken occasionally. In these cases, you will certainly come back refreshed for the rest of the day. However, don't let night work and daytime naps become a routine. Make sure this is done as an exception for unusual days.
3. When naps should be avoided
There is one big case where naps should be avoided as much as possible: in people with insomnia. It seems a little pointless: people with insomnia find it difficult to sleep at night and end up being very tired and sleepy during the day. So why stop them from sleeping during the day?
To understand this relationship, we must understand an important concept: sleep pressure. The longer we stay awake, the more our brain needs sleep. When we wake up, the need for sleep is very small, but it builds up throughout the day as we stay awake, and by night it is high enough for us to be able to sleep. This cumulative need for sleep is sleep pressure.
People without insomnia fall asleep at night for two reasons: 1. Because sleep pressure is higher at night and 2. Because our brains understand the lack of light as a stimulus to sleep. However, in people with insomnia, there is greater resistance to sleep pressure. Several cognitive and behavioral factors mean that even with high sleep pressure, the person cannot sleep. Sleep in insomniacs will only occur when the sleep pressure is extremely high, enough to be stronger than thoughts, worries, fears, anxieties or any other factors that prevent them from sleeping.
That's where napping comes in: when you get some sleep in the middle of the afternoon, the sleep pressure that had been building up throughout the day dissipates. Thus, when the night comes, at the time the person should sleep, the sleep pressure is still very low. As a result of napping in the afternoon, the onset of sleep at night is even more delayed. In other words, napping during the day ends up feeding even more symptoms of insomnia.
For people whose insomnia is related to anxiety, this relationship is even worse. In these cases, the daytime nap will make the person lie down even without much sleep pressure. This will increase your waking time in bed and allow more room for the time you should be sleeping to be filled with dysfunctional worries and thoughts.
One of the concerns of cognitive-behavioral therapy (the main treatment for insomnia today) is ensuring bedtime and the desire to sleep. For this, it is essential that the person with insomnia has high sleep pressure, increasing the chance of a consolidated and efficient sleep. SleepUp can help improve your sleep with therapeutic programs and monitoring with sleep diary and wearable technologies!
In short, naps can be very good or very bad, depending on the context in which they are taken. It is best to think of the extremes: they can have beneficial effects when they are done routinely, even if there is no need; or sporadically, when there is great need. Situations in between these two may not be so good, especially for people prone to insomnia.