What time is it to sleep late at night? What is the danger of staying up late?

When do you sleep late at night? What is the danger of staying up late?
To answer this question, we first need to understand the periodicity of sleep-wake.

Sleep, not that you can sleep when you want to sleep
“Day and night” usually refers to the night when a person sleeps.

But how late is it late?

For people who often or routinely stay up all night, people often refer to night owls who have poor sleep habits; on the other hand, getting up early and getting up early is a good sleep habit.

However, in fact, sleep is not simply a habit that one can dominate, but has an intrinsic biological basis.

As we all know, our sleep and awakening have obvious periodicity.

What forces drive us to sleep, and what power is waking us from sleep?

Driving our sleep – the power of the awakening cycle involves at least three things:

The accumulation of sleep stress during waking and the dissipation of sleep pressure during sleep; the circadian rhythm generated by the inner circadian clock; and the different individual time patterns; a steady-state process resulting from the interaction.

Sleep pressure, the increase in the amount of inosine produced by brain metabolism during waking is accumulating, the longer the awake time is, the more inosine in the brain, the greater the sleep pressure; on the contrary, during sleep, the brain can effectively break down inosine to dissipate Sleep pressure.

The “treasure” coffee we use most often works by inhibiting the effects of inosine by caffeine.

The circadian rhythm of sleep, driven by the circadian rhythm of sleep, is dominated by light-mediated melatonin produced by the pineal gland.

During the day, light signals suppress melatonin production, and nighttime light reduction and darkness promote melatonin production.

At a certain time point, melatonin will have a waterfall-like secretion, and the peak melatonin causes a sudden drop of drowsiness.

The awakening effect of cortisol, the most important driving force of morning awakening comes from the secretion of cortisol. Cortisol not only has the awakening effect, but also the level of body level directly determines the alertness and attention level of a person.

Some people maintain a high level of cortisol in the morning and morning, maintain the best physical and mental state during this time, and feel more refreshed after getting up. Some people learn cortisol in the afternoon or even at night. Higher levels are the prime time of an individual’s day.

Individual time type
In different individuals, the sleep circadian rhythm has different characteristics, medically known as the circadian rhythm type, or simply the time (inter) type.

Usually, there are three types of time in the crowd:

Morning type, “accustomed to” early sleep, wake up early, and achieve the best physical and mental state in the morning and morning of the day, often referred to as the Lark type.

Evening type, “like” to sleep late, get up late, and enter the best state later in the day and night, people often use night owls to call such people.

The two extreme types of circadian rhythms “time difference” are between 2 and 12 hours.

Intermediate, or flexibility, between the above two types, sleep “habits” have greater flexibility or adaptability.

The survey found that approximately 40% of adults in the population are classified as the above two extreme types, while 60% are intermediate.

Day and night definition
Therefore, “day and night” is not simply a matter of falling asleep, but also whether the natural day and night cycle is synchronized with each person’s time type. Therefore, for different people, the specific time of day and night is not consistent.

For most intermediate types, falling asleep at 23 o’clock is a day and night.

For the night owl type, it needs to be later than 24:00, and even 1 or 2 in the morning can be regarded as staying up late.

For the morning type, it is late at night when it is 22 o’clock or even 21 o’clock.

What is the danger of staying up late?
The danger of staying up late can be divided into two aspects:

Long-term health effects: long-term staying up late, the biological rhythm of the body is not synchronized with the natural world, it will affect the system of metabolism, endocrine and immunity, and increase the cardiovascular and cerebrovascular diseases, diabetes, obesity, certain cancers, and mental health problems. .

Effects of physical and working conditions: The immediate effects of staying up late to sleep are mainly reflected in the effects on mood, mental state and work ability.

Due to the lack of short-term sleep deficiency caused by staying up late, medically known as cumulative mild partial sleep deprivation, the main influence is reflected in the working state.

This type of sleep deficiency has received more and more attention in recent years, and a large number of studies have confirmed that this lack of sleep can significantly affect people’s cognitive function.

The biggest impact is the destruction of attention, manifested in decreased daytime alertness, lack of concentration, and drowsiness.

Second is the executive function aspect, which is the most prominent working memory, and long-term memory.

There is a huge difference in the influence of day and night on the functional status of individuals of different time types.

The study found that this effect is determined not only by the total sleep time, but also by whether the test time is synchronized with the optimal state of the time.

When the test time is synchronized with the individual alertness peak, the cognitive performance is better, which is called the synchronization effect.

Since day and night have different effects on different time-type individuals, people should appropriately arrange their own work schedules according to their own characteristics to obtain the best health and working conditions.