How to optimize your sleep quality‍

Healthy sleep is one of the most important - and at the same time most neglected - aspects of our daily lives. Surveys show that every second person in Switzerland experiences sleep problems [1]. The reasons for this are diverse: Unhealthy eating habits, overworking or mental health challenges can contribute to situations where you're tired but can't sleep.

In this article, we’ll explore how sleep impacts key health factors like your immune system, metabolism, and cognitive performance – and share actionable, science-backed strategies on how to sleep better.

Our goal is to help you wake up feeling refreshed and ready to tackle the day.

Does sleep impact longevity?

A 2023 study by Li and colleagues [2], published in QJM: An International Journal of Medicine, showed that sleep quality is strongly associated with life expectancy. The researchers analyzed data from more than 172'000 U.S. adults who participated in the National Health Interview Survey and were followed for mortality outcomes. They created a “healthy sleep score” based on five predefined low-risk sleep behaviors:

• An ideal sleep duration of 7-8 hours
• Rarely having trouble falling asleep
• Few sleep interruptions during the night
• No sleep medications
• Feeling rested after waking up

People who scored well on all five factors had a 30% lower risk of mortality. Life expectancy increased by 4.7 years for men and 2.4 years for women. Moreover, approximately 8% of all deaths were attributed to poor sleep habits. These findings show that not only is sufficient sleep important, but quality is paramount.

What happens when you sleep

While you sleep, your body is working hard to regenerate you in various ways:

Immune system

During sleep, your immune system performs at its peak. It produces defense cells and cytokines that are essential for fighting off infections. People with sleep deficiency are more susceptible to infections and take longer to recover [3]. That’s why, when you’re sick, you feel an increased need for sleep - your body is demanding the time it needs to fight the infection.

Cognitive functions and memory

Sleep is important for your mental performance. While you sleep, your brain consolidates and reorganizes memories [5]. After a good night’s rest, you’ll find that you can:

• Absorb and process new information more effectively [6]
• Think more creatively and solve problems with ease
• Focus better and regulate emotions more efficiently [7]

Chronic sleep deprivation, however, can lead to concentration difficulties, reduced problem-solving abilities, and memory disorders [8].

Physical recovery
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Sleep plays a central role in the body’s repair and recovery processes. Particularly during the deeper stages of sleep, the body shifts toward restoration: damaged tissue is repaired, proteins are synthesized, and cells perform maintenance tasks that are difficult to carry out during waking hours. This nightly recovery cycle supports several important processes:

• Training places stress on muscle fibers, and sleep provides the conditions in which the body can rebuild and strengthen them. Even one night of partial sleep deprivation impairs recovery from a single exercise session [9].
• Research shows that poor sleep quality can slow wound healing and impair the body’s ability to repair damaged tissue [10].
• Consistent, high-quality sleep supports normal bone remodeling, while chronic sleep disruption has been associated with impaired bone metabolism and reduced bone health [11].

Without sufficient high-quality sleep, recovery from exercise, illness, or injury may take longer, and the body’s ability to adapt to physical stress can be compromised.

Hormone balance and regulation

Sleep influences the production and release of many hormones [17]:

• Melatonin: The “sleep hormone” is released in darkness and regulates your sleep-wake rhythm [18].
• Serotonin: This “happiness hormone” is produced in daylight and contributes to your mood and well-being.
• Growth hormones: Released during deep sleep, they promote cell regeneration and growth.
• Cortisol: This "stress hormone" decreases during sleep and rises in the morning to prepare you for the day.
• Leptin and Ghrelin: These "hunger and satiety hormones" become imbalanced through sleep deprivation, which can lead to increased feelings of hunger.

A balanced hormone production is vital for your energy levels, mood, and overall health – and significantly depends on sufficient, high-quality sleep [19].

Tips to sleep better long term

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While there’s no “on-off switch” for sleep, there are surprisingly effective strategies to improve your sleep quality - especially if you regularly struggle to fall asleep or wake up feeling unrested.

Stick to a consistent sleep schedule

Your body loves rhythm and consistency. Try to go to bed and wake up at the same time every day. 1 or 2 nights of catch-up sleep on the weekend can be helpful (and are recommended) [20], but throwing your bedtime overboard can have negative effects. Studies show that a stable sleep-wake rhythm supports your body's internal clock and regulates the release of the sleep hormone melatonin. Aim for 7-9 hours of sleep daily, depending on what you personally find most restorative.

Find your perfect sleep temperature

Temperature is a cornerstone of sleep hygiene. Scientists use the term "ambient thermoneutrality" to describe the sweet spot where your body perfectly maintains its core and skin temperatures without needing to sweat or shiver [21]. While this range is around 28°C (82°F) for those sleeping without clothes or bedding, most of us use blankets and pajamas. Heat is more disruptive to our sleep architecture than cold, largely because blankets allow us to manually adjust to cooler rooms, whereas excess heat leads to frequent night-waking.

Interestingly, men often prefer cooler temperatures than women. For their most restorative sleep, both need to balance their room’s ambient temperature with their bedding’s microclimate, to find their sweet spot. When in doubt, lean towards slightly cooler.

Make it dark, make it silent

Your bedroom should be a sensory sanctuary. Research shows that noise and light are the two primary environmental disruptors that can "reset" your internal clock or cause unwanted night-waking [21].

Frequent noises above just 35 dB - roughly the volume of a whisper or a quiet library - are enough to reduce both sleep quality and quantity. To combat this, try to locate your bedroom away from high-traffic common areas. If you live near a highway, railway, or airport, focus on sound-attenuating measures like heavy doors or insulated windows. If outside noise is unavoidable, using continuous white noise can help mask these disruptions and keep you in a deeper sleep state.

Light impacts you in two ways: it causes immediate waking and it resets your "circadian pacemaker," shifting your entire sleep schedule. Our systems are incredibly sensitive; exposure to even 65 lux (about the brightness of a dim hallway) can delay your melatonin production by a full hour.

Step away from screens

A major systematic review and meta-analysis published in JAMA Pediatrics [23] suggests that devices like smartphones and tablets are among the most significant threats to sleep hygiene. The study, which analyzed data from over 125’000 children and adolescents, found that using a screen-based device near bedtime more than doubles the risk of inadequate sleep quantity and significantly increases the odds of poor sleep quality and excessive daytime sleepiness.

The most surprising finding? Simply having access to a device in the sleep environment - even if it isn't used - is strongly associated with poor sleep outcomes. The mere presence of a smartphone can cause "psychophysiological arousal," keeping the brain in a state of alert anticipation for notifications or social interactions. To truly optimize your recovery, the best strategy is to keep your devices in a separate room entirely once you head to bed.

Move more

Regular exercise is one of the most effective tools for improving sleep. A large-scale meta-analysis in Frontiers in Psychiatry [24] confirms that consistent activity significantly reduces insomnia severity, daytime sleepiness and improves mood. While more intense exercise such as cycling showed effects within a few days, lower-intensity activity and mind-body exercises like yoga needed a longer intervention time to show significant effects.

Eat your way to better rest

What you eat directly influences your brain’s ability to transition into sleep. Research [25]  highlights that diets rich in tryptophan - an amino acid found in milk and eggs - are associated with faster sleep onset and higher sleep efficiency. This is because tryptophan is a precursor to serotonin and melatonin.

Cherries can be equally effective; they contain high concentrations of melatonin and phytonutrients that have been shown to increase total sleep time. Pairing these with carbohydrates-rich foods roughly four hours before bed can further help tryptophan cross the blood-brain barrier, effectively prepping your system for deep, restorative rest.

What to do if I’m tired but can't sleep?

If you’re lying in bed and struggling to fall asleep, mindfulness practices such as meditation, breathwork, guided imagery or journaling can help you save the night [26]. Here, we’d like to show you our two favorite ones:

Slow Paced Breathing

Controlling your breath is a direct way to communicate with your nervous system. Research published in Psychophysiology [27] shows that slow, paced breathing at a frequency of 0.1 Hz (one breath every 10 seconds) significantly increases "vagal activity," effectively switching your body from an alert state to a rest state. Practicing this for 20 minutes before bed has been shown to reduce the number of night-wakings and significantly shorten the time it takes to fall asleep.

How to perform it:

• Find a comfortable position and close your eyes.
• Inhale slowly through your nose for 4 seconds.
• Exhale gently through your mouth for 6 seconds.
• Maintain this steady rhythm for 20 minutes

Progressive Muscle Relaxation

Oftentimes, we don't realize how much physical tension we are carrying until we actively try to release it. Progressive Muscle Relaxation (PMR) is a technique to systematically tense and then release different muscle groups. A study in Complementary Therapies in Medicine [28] found that a consistent PMR practice significantly improves sleep quality and efficiency. By focusing on the physical sensation of relaxation, you effectively "quiet" the mind and prepare the body for deep recovery.

How to perform it:

• Lie on your back in your quiet, dark bedroom.
• Starting with your feet, tense your muscles tightly for 5 seconds.
• Quickly and completely release the tension for 10 seconds, focusing on the feeling of relaxation.
• Move systematically up your body - through your calves, thighs, stomach, and hands - until you reach your face.

When you’re done, you should fall asleep within a couple of minutes.

How AYUN can help you sleep better

At AYUN, we view sleep quality as part of a comprehensive health picture and help you optimize your relevant factors with our personalized approach.

First: Diagnose

Our check-ups provide deep insights into the factors affecting your sleep:

• Blood Analysis: Nutrient deficiencies like magnesium can directly impact your sleep [22].
• Heart Rate Variability: This measurement reveals your individual stressors and how your nervous system responds to them [28].
• Gut Microbiome: Analysis can identify inflammation processes that may disrupt sleep [3].

Second: Treat

Based on your results, we may recommend targeted treatments:

• Red Light Therapy: By naturally improving serum melatonin level, red light therapy supports a healthy sleep-wake cycle [29].
• Cryotherapy: Reduces systemic inflammation and shifts the body into a parasympathetic (rest-and-digest) state, which has been shown to improve subjective sleep quality [30].
• HBOT (Hyperbaric Oxygen Therapy): Enhances oxygen saturation and reduces oxidative stress in the brain, helping to increase total sleep efficiency [31].
• Contrast Therapy: Alternating between heat and cold improves circulation and aids in body temperature regulation, which is essential for falling asleep quickly [32].
• ExerCube: This form of high-intensity cognitive-motor training has been shown to increase the duration of deep sleep stages [33].

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Additionally, certain evidence-based supplementation formulations can support sleep stability, particularly in individuals experiencing stress-related nighttime awakenings or difficulty maintaining deep sleep.

In collaboration with AVEA, a Swiss longevity-focused supplement company, we explore melatonin-free, non-sedative approaches designed to support cortisol balance and calm neurotransmitter pathways such as GABA. Unlike traditional sleep aids that primarily focus on sleep onset, these formulations aim to support sleep depth and continuity. This approach is intended to complement, not replace, personalised clinical evaluation and treatment.

At AYUN, we focus on long-term solutions, not quick fixes. We help you identify the root causes of sleep issues rather than just treating symptoms. Learn more about how our Longevity Check-ups and treatments can improve your sleep and overall health during a free info call.

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