Sleep well: restful sleep

While we are lying quietly in bed, a firework of activities rages inside us. They make us fit for the next day and keep us healthy

Sleep really well - for memory and immune protection

© Shutterstock / New Africa

Six nights with full board, all meals in your room and $ 1,000 in your pocket. A tempting offer. But those who got involved did not experience a vacation. The hotel guests were participants in an experiment by sleep researchers in the USA.

The test subjects inhaled a nasal spray with a cold virus and spent the following five days in the hotel, shielded from it. As expected, some of them caught a cold. But those who slept an average of less than six hours at night had a 4.5 times higher risk.

Sleeping strengthens the immune system

The study shows: Sleep is important for the defense against pathogens. Our immune system works at full speed at night. And long-term immune protection apparently also benefits from this.

The team led by Professor Jan Born from the University of Tübingen was able to demonstrate this using the example of hepatitis vaccinations. "A year later, those who did not sleep the night after the Pikser had only half as many immune cells against hepatitis viruses as their peers," the scientist summarizes the results.

There are many sleep myths - our explanatory video clears up some of them:

The day in a fast run

Even if we don't notice anything, a lot happens in our body at night too. Only a few years ago it was discovered that the brain and spinal cord have a coherent disposal system. It removes pollutants - especially when you sleep - that have accumulated during the day.

In addition, the memory is strengthened. Nerve connections that are activated during the day are strengthened, those that are not used are weakened. To do this, the brain replays important events from the previous day. The same nerve cells fire in the same sequence - only ten times faster.

"Dreams, on the other hand, have the same pace at which we experience things," says Dr. Martin Dresler, sleep researcher at Radboud University Nijmegen (Netherlands). He therefore considers it implausible that they play a major role in memory formation.

Dreams: space to try out and experience

In any case, some researchers regard dreams only as an accessory to brain activity - irrelevant. On the other hand, the nocturnal head cinema has something to do with the person of the dreaming. It is often surreal, more emotionally charged and eventful than what actually happened.

Some experts suspect that dreams offer us space to safely practice new behaviors. Dresler: "We can try everything in dreams without risking our lives or making a fool of ourselves in front of others." For example, fighting lions or bluntly saying what people think of you who piss you off.

But why do we lose consciousness as soon as we fall asleep? We are then exposed to real threats without protection. "Presumably we have to be decoupled from the outside world, otherwise certain sleep processes could not take place", says Dresler: the memory building, the brain cleaning and the dream experience.

Bad sleep indicates illness

One thing is certain: we need sleep, it keeps us healthy. If it is too short or not restful, the next day we feel tired, irritable and inattentive. If this happens frequently, the quality of life decreases. Poor sleep can also be a sign of illness.

Conversely, chronic lack of sleep promotes high blood pressure, depression, dementia, type 2 diabetes and obesity. Therefore speak to your family doctor about sleep problems! A questionnaire can help to assess your own sleep quality.

Video: tips for getting a good night's sleep

The power of negative thoughts

One of the greatest troublemakers during the night are negative thoughts. "There are a lot of people who brood over their sleep every night, making it difficult for them to rest," says Professor Kai Spiegelhalder from the board of the German Society for Sleep Research and Sleep Medicine.

But that usually makes the problem even worse. A cycle begins: those affected are afraid of going to bed, are even more unable to switch off, fall asleep even worse, and worry even more.

Psychotherapist Spiegelhalder recommends not to worry too much. Anyone who tackles the problem need not fear serious health consequences.

Regulated sleep

Habits play a major role in the quality of sleep: "That's crazy! I fell asleep better with you, because it's so boring here!" - Professor Kai Spiegelhalder hears this or something like that over and over again - from people who suffer from insomnia and therefore come to him at the Freiburg University Hospital.

Professor Kai Spiegelhalder, German Society for Sleep Research and Medicine

© W & B / Bernhard Kahrmann

They then spend a night or two there - connected to devices that measure sleep, but disconnected from television and the Internet. Spiegelhalder: "Many patients are amazed at the effect this has on them."

Small changes are often enough to improve the night's sleep. (There are small suggestions in the boxes below.) However, there are no recommendations that work for everyone. "Everyone should try out what works best for them," advises sleep and memory researcher Dr. Martin Dresler from Radboud University in Nijmegen (Netherlands).

About coffee, alcohol and sleeping pills

People react differently to possible triggers of sleep problems. For example, on the stimulant caffeine. Some people fall asleep better if they go without coffee from midday onwards, while others feel no effect at all.

For alcohol, on the other hand, the situation is clear. "Although it helps you fall asleep, it disrupts sleep in the second half of the night," says Dresler. You wake up again and find it difficult to get back to sleep.


Cell phones do not allow many people to relax. The blue light contributes to this. Many devices can be dimmed. Better: switch off

And how about sleeping pills? Experts agree: Doctors should be cautious about prescribing drugs to their patients - most substances only for a short time.

Dresler explains why: "With so-called benzodiazepines and the similarly acting Z-substances, habituation effects become apparent very quickly, and a higher dose is required after just a few days."

And those who take the medication over a longer period of time will find it difficult to get rid of them. Dresler: "As soon as you take it off, your sleep disorder is worse off than before."

Natural sleep aids

Many people first turn to a pharmacy with their problem. There you can help with over-the-counter products. However, there are also a few things to consider with these, for example with herbal medicines with valerian root, hop cones, lemon balm leaves or passion flowers.

Dieter Wohlert, pharmacist in Emden

© W & B / Mario Wezel

"Herbal products need a few days to take effect," says Dieter Wohlert, a pharmacist in Emden. "But you can take them over a longer period of time without any problems." But the preparations only have a weak sleep-promoting influence.

Note side effects

Synthetic antihistamines, also available over the counter, are more effective, but have some side effects. The most common are drowsiness, lightheadedness and dizziness, muscle and headaches, skin reactions and gastrointestinal problems.

If you stop taking the medication after a long period of daily use, you will have to reckon with poor sleep again. "For these reasons, you can take them for a maximum of two weeks," says Wohlert. There are also conditions such as prostate enlargement for which antihistamines should not be taken.

Clarify the causes with a doctor

For patients who repeatedly ask for sleeping pills, the pharmacist's main advice is: "Go to the doctor to clarify the causes and treat them specifically." Because sleep disorders can have many reasons, and nobody should spend an unnecessarily long time in uncertainty.

The first point of contact is usually the family doctor. For example, he uses a blood test to check whether there is an overactive thyroid and, if necessary, refers the patient to a specialist for further examinations.

In the sleep laboratory, for example, doctors check whether there are nocturnal pauses in breathing (sleep apnea) or other physical causes. Therapy then depends on the diagnosis.

Relearn how to sleep

However, doctors do not always find a disease to be the cause. Or the disease is treated successfully, but the sleep problems remain. In these cases, the treatment guidelines recommend cognitive behavioral therapy from a psychotherapist. "This is actually old hat, but extremely effective," says Spiegelhalder.

Tips for the day

The therapist teaches the basics about sleep: for example, that the need for it varies from person to person and is between five and nine hours. The patients also learn methods that help them to relax, to structure their sleep-wake cycle better and to brood less in bed. A total of four to eight meetings are planned.

But unfortunately there are far too few therapy places. The Federal Joint Committee has also recognized this. The committee is currently promoting the development of an online service that is intended to close the supply gap. If it proves helpful, it could be generally available in 2024. Anyone affected with Internet access could then use it.

Sleep later, get up earlier

Those who have enough motivation and perseverance can also try to improve their sleep quality on their own. Spiegelhalder: "It is not rocket science what happens in cognitive behavioral therapy. A lot falls into the area of ​​tips and tricks."

In his opinion, word of one important, particularly effective measure has not gotten around so far: to bed half an hour later in the evening or to get up half an hour earlier in the morning - for a week.

This means that you are more tired during the day, but you fall asleep more easily in the evening and then also feel better during the day. Spiegelhalder: "Very few have tried it out consistently. Many are very surprised that it allows them to regain a certain amount of control over their sleep."

Tips for evening and night

  • Wait for the tiredness and only go to bed when the need for sleep is acute.
  • The bedroom should be quiet, darkened, cool and well ventilated.
  • Make sure you have a comfortable mattress, duvet and pillow.
  • Stop the flood of stimuli. Switch off the television, computer and smartphone in good time and deposit them outside the bedroom. Mental and emotional stimuli keep you awake.
  • Rituals help you come down and fall asleep, for example a warm bath or a cup of fruit or herbal tea.
  • Relaxation techniques such as autogenic training, progressive muscle relaxation or meditation are also useful and can be learned.
  • Avoid sleeping pills and use them very sparingly.
  • Alcoholic beverages are not suitable as a nightcap. It is best to avoid it completely, even during the day. Especially in combination with sleeping pills, it is absolutely necessary to do without it.