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A collaborative effort by Helmholtz Munich, the German Diabetes Center, and the German Center for Diabetes Research

Healthy sleep strengthens body and soul

Scientific support: Prof. Dr. Michael Hummel

Healthy sleep means sleeping long enough and without interruption. This is the only way for body and mind to recover undisturbed. Poor sleep usually manifests itself immediately, for example through symptoms such as irritability or tiredness the next day.

In the long term, sleep problems can be a serious threat to health and increase the risk of diseases such as type 2 diabetes, obesity, depression, and cardiovascular disease

The good news: There are many ways to promote your sleep and health. This includes, for example, paying attention to the right sleeping environment, not eating too late or drinking caffeine. If the sleep problems persist, it is important to seek medical help. This helps to avoid the negative effects of poor sleep on health.



1. What is healthy sleep?

Sleep is one of the greatest unsolved phenomena we know. Experts have still not been able to clarify every detail. However, one thing is certain: Sleep has an effect on practically all systems of the body. Sleep allows us to replenish our energy reserves, process and store what we have experienced – it is important for our mental and physical development.

While we sleep, our body temperature and brain activity decrease. The heart rate and breathing also slow down. However, the body only appears to come to rest, as certain regeneration processes in the body are particularly active during this phase. They allow the brain and body to recover. Among other things, our brain processes what we have learned and consolidates memories, body cells regenerate and the immune system is strengthened. Healthy sleep is important to ensure that these processes can take place undisturbed.

But when is sleep healthy? On the one hand, healthy sleep means sleeping long enough. How much sleep is needed depends mainly on age: Babies initially sleep 16 to 18 hours a day to promote growth and development, especially of the brain. School-age children and adolescents need an average of around 9.5 hours of sleep per night. For most adults, however, 7 to 9 hours are enough. On the other hand, the quality of sleep is just as important as the duration of sleep.

Good to know:

Every 2nd adult in Germany gets a maximum of 6 hours of sleep per night. Experts agree: That is not enough. The amount of sleep required varies from person to person, but on average adults need 7 hours of sleep.

Sleep is a dynamic process that is made up of a precise sequence of different sleep phases.

There are basically two different types of sleep:

  • Non-REM sleep (non-rapid eye movement sleep): Sleep phase without rapid eye movements
  • REM sleep (rapid eye movement sleep): Sleep phase with rapid eye movements, also known as dream sleep

 

A sleep cycle consists of the following phases:

  • Non-REM phase with a total of 3 stages:
    • Stage 1 = falling asleep phase
    • Stage 2 = light sleep
    • Stage 3 = deep sleep
  • REM phase (deep sleep)

 

Normally, the individual sleep phases of a sleep cycle take place in a typical sequence. After falling asleep, there are usually several phases of light sleep and deep sleepbefore a REM sleep phase completes the respective cycle. One cycle takes about 90 minutes. The body can best benefit from going through all these sleep phases several times a night – there are 4 to 5 cycles per night.

The different stages of sleep are important for the regeneration processes in our body and brain. If you are constantly waking up, you disrupt this process and thus also the restorative effect of sleep.

Signs that your sleep is not restful can be:

  • Poor responsiveness
  • Difficulty concentrating
  • Increased irritability
  • Difficulties in solving problems
  • Reduced memory
  • Not feeling rested even though you have slept enough
  • Tiredness on waking

A lack of sleep can also make you doze off more easily during the day – especially in situations where you are not active, for example when watching TV, reading or at the movies.


2. Why is healthy sleep so important for your health?

Everyone sleeps badly sometimes; that's not a problem in itself. However, if poor sleep occurs repeatedly and over a longer period of time, this can have negative consequences for your health.

Lack of sleep increases the risk of stroke and heart attack

Poor sleep disrupts the metabolism and the hormonal system. The result: Blood pressure rises and there is an increase in inflammatory factors in the blood. This can put a strain on the cardiovascular system. In the long term, lack of sleep increases the risk of a heart attack and stroke. People who work shifts are particularly at risk.

Lack of sleep: Risk factor for obesity

People who sleep too little on a permanent basis also have an increased risk of developing obesity. The shorter the sleep duration, the higher the probability of obesity. The mechanisms behind this connection are not yet entirely clear. However, experts suspect that a lack of sleep increases appetite, increases the feeling of hunger and leads to a higher consumption of sweets.

Type 2 diabetes due to lack of sleep

Sleep duration also has an influence on the risk of diabetes. Both short nights (5 to 6 hours per night) and sleeping too long (more than 9 hours per night) increase the risk of developing type 2 diabetes. Researchers suspect that an altered metabolism plays a role in this context.

Poor sleep can make you depressed

Poor sleep increases the risk of becoming mentally ill later in life. Depression and anxiety disorders in particular occur more frequently. Suspected causes for this include among others:

  • A hormonal system that is out of balance
  • Elevated inflammation levels in the blood
  • Problems with mental performance due to lack of sleep
  • Impairment of mood due to lack of sleep

Good to know:

Stroke, obesity and type 2 diabetes – lack of sleep is a risk factor for various diseases. The good news: There are many ways to promote healthy sleep and therefore health.


3. 12 tips for better sleep

Whether it’s stress, noise or too much coffee – the causes of poor sleep can be varied. Various sleep-promoting strategies can positively influence the triggers and disruptive factors. In this context, reference is often made to good sleep hygiene.

Below you will find 12 tips to help you fall asleep and stay asleep:

Tip 1: Allow sufficient time.

It is generally advisable to always provide for enough time for sleep. Sleep is often the first thing that busy people in particular cut from their schedule. Make sure youhave enough time for sleep and avoid seeing sleep as a “necessary evil”.

Tip 2: Find an evening routine.

Try to avoid stressful activities such as working late. This way you don’t transfer the demands you experienced during the day into the evening. Instead, look for an activity that lets you relax. A hot shower, reading or a cup of tea – everyone needs something different to end the day and start the night with a relaxed feeling. Important here: Stop watching TV two hours before going to bed andavoiddevices with blue light (laptop, smartphone, tablet).

Tip 3: Set up your bedroom properly.

Create a pleasant atmosphere in your bedroom. Above all, make sure that the room is sufficiently dark. Avoid bright lights and make sure the windows are well darkened. Only use your bed for sleeping. Electronic devices such as televisions and computers should not be in the bedroom. What also helps: It should not be too warm and as quiet as possible. Also make sure you have a comfortable mattress, pillow and blanket.

Tip 4: Stay calm.

When you wake up at night, try not to look at the clock – this will only put you under pressure. This in turn creates inner tension and usually makes it even harder for you to fall asleep and stay asleep. If you have trouble falling asleep, it is better to get up and read or listen to music until you are tired again.

Tip 5: Make sure you relax.

Targeted relaxation can help with sleep disorders – for example with progressive muscle relaxation, mindfulness exercises or fantasy journeys. Aromatherapy can also be suitable for relaxation. The inhalation of fragrant oils has a direct effect on the central nervous system, which is responsible for controlling emotions and physical functions. Lavender oil in particular is often used for sleep problems.

Tip. 6: Don’t eat too heavily and don’t eat dinner too late.

A full stomach is busy digesting and can prevent you from sleeping. It is therefore better to avoid very fatty, rich meals in the evening and to avoid eating just before going to bed.

Tip 7: Find your sleep rhythm.

Humans are creatures of habit, and this also applies to sleep. So go to bed at the same time every night and get up at the same time every morning if possible – even at weekends and on vacation. This helps the internal clock to stay in balance.

Tip 8: Do not drink caffeine too late.

If you find it difficult to relax and fall asleep in the evening, avoid drinking caffeinated drinks such as coffee, Coke or black tea after lunch.

Tip 9: Exercise regularly.

Physical activity, preferably in the open air, reduces stress hormones and makes you pleasantly tired. Important: However, you should not do any strenuous sport too late in the evening, as this activates the body and makes it harder for you to fall asleep. But a relaxed walk is no problem.

Tip 10: Avoid sleeping during the day.

If you don’t sleep well at night, it’s better not to compensate for the lack of sleep with a nap during the day – even if it’s difficult. If there is no other way: Take a nap before 3 p.m. and no longer than 20 minutes.

Tip 11: Do not use alcohol as a sleeping pill.

Alcohol isn’t helpful if you can’t fall asleep. Although it usually helps you to fall asleep more quickly, alcohol also reduces the general quality of your sleep and you wake up more often at night. It is therefore best not to drink any alcohol, or only a little, and preferably not just before going to bed.

Tip 12: Keep a sleep diary.

For example, you can note down when you go to bed, what you ate in the evening or how often you woke up during the night. This can give you an overview of how much you actually sleep and also help you to recognize bad habits.

Good to know:

Often, it is not possible to realize healthy sleep from one day to the next. It requires patience, perseverance and the consistent implementation of tips to achieve better sleep hygiene.


4. What needs to be considered in case of sleep disorders?

Temporary sleep problems are common and medical treatment is not necessary in most cases. However, if symptoms such as problems falling asleep despite being tired or waking up frequently during the night persist for a long time, it is important to seek help. Experts speak of a chronic sleep disorder (chronic insomnia) if the symptoms occur at least 3 days a week over a period of at least 3 months.

You should definitely take persistent symptoms seriously, as they increase the risk of serious health consequences such as a heart attack or stroke. It is also possible that the sleep disorders are caused by a physical or mental illness. This should be clarified by a doctor. Doctors also know best what to do in the event of extreme sleep disorders.

What treatment options are there for severe sleep disorders?

As a rule, psychotherapeutic treatment (cognitive behavioral therapy) is used first. If this is not possible or does not bring the desired success, various medications are available. As they can be addictive, affected persons should only take them as prescribed by a doctor.

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As of: 07.05.2024