What happens to your body when you sleep 7-8 hours a day

With each passing decade humans sleep less. The many distractions and needs of modern life, the fear of not being able to manage everything and concern for the future have been considered the great villains of the night’s sleep.

  • 65% of the population reports having problems related to sleep
  • 20% of people aged 25-45 slept 90 minutes less than they needed to stay healthy
  • In the last 3 decades there has been a reduction of up to 18 minutes of sleep per night

But should sleep health be measured only by the number of sleepless nights? Healthy sleep is one that combines personal satisfaction, adequate time, adequate duration, ease of falling asleep or returning to sleep, sustained attention during hours of activity, as well as the absence of disorders such as insomnia.

To promote physical and mental well-being, this model must adapt to personal, social and environmental needs.

  • Most people need 7-9 hours of sleep (adults) or 7-8 (seniors); a minority, the late sleepers, can sleep 4 to 5 hours without harm.
  • Sleep insufficiency should not be confused with insomnia, one of the most common sleep disorders. While the first can be voluntary, in the second the person is unable to fall asleep despite the presence of favorable conditions.
  • More is not better: Studies show that sleeping more than 9 hours a night increases the risk of premature death, stroke and heart disease.

What do you get

Sleep is a complex biological process and essential for maintaining life for people of all ages.

Sleep consists of non-REM and REM phases, and is controlled by an internal biological clock that controls the alternation between sleep and wakefulness.

When this process is not fragmented, it promotes the restorative action of health and function necessary to ensure an active day. The benefits are widespread and long-lasting:

  • Longevity
  • Increases the body’s defenses
  • mood improvement
  • More balance on the scale
  • Updated cognition
  • less headaches
  • anti-aging brain
  • Increased empathy, reduced impulsivity

live longer

Getting enough sleep prevents premature deaths from various types of diseases. And it is not known which comes first: cardiovascular problems or insufficient sleep.

A study called The sleep heart study concluded that conditions leading to short-term rest increase the risk of having a heart attack and stroke, diseases that top the list of causes of death in Brazil.

Sleepless nights are linked to the malfunction of the neuro-endocrine-metabolic systems and inflammatory processes. They are all linked to high blood pressure, obesity, as well as high blood cholesterol and glucose levels.

Insulin resistance, a hallmark of diabetes, has also been linked to sleep deprivation among patients with type 1 (especially younger ones) and type 2.

You protect yourself from infections

The research area that studies the interactions between the immune system and sleep is still recent, but it is already known that sleep is a sacred medicine to protect against infections of all kinds, including those of the respiratory tract. It is no coincidence that all of these conditions have the feeling of tiredness and sleepiness as common symptoms.

Scientists from the universities of Harvard, Tübingen and Lübeck state that sleeping well seems to promote the body’s defenses against inflammatory processes and that quality sleep before and after vaccination was associated with better levels of immunity. The study was published in the journal Physiological reviews.

You are in a better mood

Who sleeps well wakes up well. Who sleeps badly, wakes up badly. Adequate sleep time keeps hormones in check and its opposite increases cortisol levels, related to stress and constant alertness.

Since anxiety, depression and insomnia always go hand in hand, treating the disorders and getting quality sleep is the key to preventing or alleviating these disorders.

Keep your weight under control.

Getting 7-8 hours of rest a night helps maintain a healthy weight. When scientists compared people who get 7 hours of sleep with those who get short sleep durations, the chance of weight gain among those who sleep less was nearly 10 percent higher for every hour of sleep lost.

Poor nights of sleep reduce your metabolic rate, which increases cortisol and ghrelin levels. These hormones make room for hunger. The result is a frequent and intense craving for more carbohydrates and sugar, especially at night. The diet is affected in quantity and quality.

You have the sharpest brain

Sleeping well guarantees the ability to think clearly, learn, be alert and concentrated, not to mention the maintenance of memory, which consolidates during the rest period. After 16 consecutive hours of sleep deprivation, all of these benefits diminish and the negative effect accumulates.

You avoid headaches

Migraines are more common among people with sleep disorders such as sleep apnea. More hours in bed reduce the chances of having acute or chronic episodes over time, especially among the elderly and people with obesity. The data was published in the medical journal headache.

Contribute to a “cleansing” in the brain

Recent research has examined the value of sleep for the glymphatic system. Regulates the flow of cerebrospinal fluid (which waters the brain) in the brain parenchyma, which is responsible for the development of brain function.

Tasked with doing a local cleanse overnight, this system aims to remove metabolic wastes from local cells, already linked to neurodegenerative diseases.

Knowledge of this process is still ongoing. It is estimated that, soon, it will be possible to prevent diseases such as Alzheimer’s, as well as delay the aging of the brain. The data was published by the journal Brain sciences.

Get more regulated emotions

By investing in proper rest, you save yourself from troubles and confrontations in your personal life and at work. Sleep deprivation impairs the processing of emotion data, which reduces empathy in interpersonal relationships; even sleepless nights increase impulsivity and this combination is considered explosive.

Does a pill help?

It may seem easy to take drugs instead of changing habits, but using drugs alone does not solve the problem. They are useful and only indicated until sleep hygiene and stress control measures can be implemented.

The onset of sleep should occur in 10, 20 and 30 minutes. Not tolerating this wait generates anxiety, which hinders the initiation and maintenance of rest. Falling asleep after 30 minutes can be associated with insomnia.

Excessive awake time refers to several medical situations and conditions:

  • Anxiety
  • Depression
  • Destructive feelings and frustration
  • Irritability
  • lack of concentration
  • low motivation
  • organizational deficit
  • sedentary lifestyle
  • Hypertension
  • Hyperlipidemia (high levels of cholesterol and triglycerides)
  • to smoke
  • Obesity
  • Road and workplace accidents
  • hormonal changes
  • Diabetes
  • coronary artery disease
  • arrhythmias
  • Gastroesophageal reflux
  • attention deficit
  • stroke
  • Memory and learning difficulties

Tips for getting more and better sleep:

  • Adopt a regular exercise schedule, but avoid night shifts.
  • Minimize night sounds as much as possible
  • Set a specific time to sleep and wake up
  • Cut naps longer than 45 minutes during the day
  • Prefer light meals with delicate seasonings and avoid sweets at dinner
  • Avoid alcohol and caffeine 4 to 6 hours before bed.

Sources: Alan Luiz Eckeliprofessor of neurology and sleep medicine at FMRP-USP (Ribeirão Preto School of Medicine, University of São Paulo); Alexander Ararunapulmonologist, specialist in sleep disorders and member of the clinical staff of HULW-UFPB (Lauro Wanderley University Hospital of the Federal University of Paraíba), which is part of the Ebserh network (Empresa Brasileira de Serviços Hospitalares); Beatrice Mota Sampaio, general practitioner at the Population Health Department of the Sírio-Libanês Hospital (SP); And Gisele Richter Minhotopsychiatrist, sleep medicine specialist and lecturer at the PUC-PR School of Medicine. Medical Review: Alan Luiz Eckeli.


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