How dry cabin air affects your fatigue and sleep

Flying should be an enjoyable experience, but the dry air in airplane cabins can often leave you feeling fatigued and struggling to sleep. In this article, we explore how the low humidity levels standard in aircraft can dehydrate your body and brain, leading to discomfort and tiredness. Fortunately, CTT Systems Humidifier Onboard is making strides to improve in-flight comfort and health, ensuring you arrive at your destination more refreshed and well-rested.
How dry cabin air affects your fatigue and sleep - by CTT Systems
Table of Contents

Why is airplane cabin air so dry?

Airplane cabins typically have a low humidity level, often as low as 5% in first and business class, compared to the usual and healthy 30-60% in most indoor environments. This low humidity results from the airplane’s high-altitude flight, where the extremely dry outside air is brought into the cabin and pressurized. 

Dry air dehydrates your body and brain

The dry air in airplane cabins leads to rapid moisture loss from the body, mainly through the skin and respiratory system. This can significantly dehydrate you throughout a flight and significantly impact your body’s ability to function correctly, increasing fatigue. 

The brain is also susceptible to changes in hydration status. Even mild dehydration can affect cognitive functions, leading to difficulty concentrating and decreased mental performance. This includes cognitive processes and increased perception, which can further degrade performance and concentration. 

Symptoms of dehydration

Dehydration during flights can manifest through a variety of symptoms, including: 

Dry mouth and throat

You often feel an unusual dryness in your mouth and throat, making swallowing uncomfortable. 

Dry skin and eyes

Insufficient moisture can cause your skin to become itchy and irritated, and your eyes may feel dry and scratchy. 


A common symptom of dehydration is headaches, which can become more pronounced during flights due to dry air and potential lack of oxygen. 

Fatigue and dizziness

Dehydration affects overall energy levels, causing you to feel exhausted and sometimes dizzy. 

The negative effects of dry cabin air on sleep

Air travel can be particularly exhausting, and one key factor contributing to this fatigue is the dry air inside the cabin. Low humidity levels can significantly affect your ability to sleep well during flights. Here’s a detailed look at how dry cabin air impacts sleep. 


This affects the mucous membranes in the nose and throat, making them dry and uncomfortable. This discomfort can lead to difficulty falling asleep and staying asleep. 

Disrupted sleep patterns

When dehydrated, the body can’t regulate its temperature as effectively. This can lead to fluctuations in body temperature, making it harder to maintain a stable, comfortable state necessary for quality sleep. You may experience frequent awakenings due to discomfort and an inability to reach deep, restorative stages of sleep. 

Respiratory irritation with dry airways

Low humidity can dry out the nasal passages and throat, leading to a scratchy throat and increased mucus production as the body attempts to protect these areas. This can cause frequent coughing and an irritated airway, significant barriers to restful sleep. 

Increased snoring and sleep apnea

Dry air can exacerbate snoring and sleep apnea in those prone to it. Dry nasal passages can lead to nasal congestion, which increases the likelihood of snoring and the severity of sleep apnea. Both conditions significantly reduce sleep quality, leading to more fragmented and less restorative sleep. 

Jet lag and Circadian Rhythms Disruption

Flying across time zones disrupts the body’s natural circadian rhythms, causing jet lag. Dry cabin air can exacerbate the symptoms of jet lag, making it even harder to adjust to the new time zone and achieve a good night’s sleep. 

The Humidifier Onboard helps you sleep better

CTT Systems’ Humidifier Onboard significantly improves in-flight comfort, effectively addressing the negative impacts of dry cabin air on your sleep and well-being. Here’s how it helps. 

Combatting dehydration

The Humidifier Onboard maintains optimal humidity levels in the aircraft cabin, significantly reducing the rate at which moisture is lost through the skin and respiratory system. 

Better hydration and overall well-being

You are less likely to experience the negative effects of dehydration, such as dry mouth, skin irritation, and overall discomfort. Staying well-hydrated supports better overall health, including improved digestion and reduced susceptibility to colds and other illnesses. This makes the flight experience more pleasant and reduces post-flight fatigue and malaise. 

Improving sleep quality

Higher humidity levels in the cabin environment help moisten mucous membranes in the nose and throat, reducing respiratory irritation. This means you are less likely to experience coughing, dry airways, exacerbated snoring, and sleep apnea, leading to a more restful and uninterrupted sleep during flights. 

Alleviating fatigue and enhancing concentration

Proper hydration maintained by the Humidifier Onboard ensures better blood volume and electrolytes. 

Mitigating jet lag symptoms

The Humidifier Onboard can also help your body stay hydrated and comfortable, reducing the severity of jet lag. You find adjusting to new time zones easier when you arrive less tired and dehydrated, allowing for a smoother transition and more enjoyable travel experience. 

Sleep better and travel comfortably with a Humidifier Onboard

In conclusion, the dry air in airplane cabins can significantly affect your comfort and health, leading to dehydration, fatigue, and disrupted sleep. Low humidity levels contribute to symptoms such as dry mouth, throat, skin, eyes, headaches, and increased snoring and sleep apnea. These factors collectively result in a less restful and more exhausting travel experience.

The Humidifier Onboard offers a practical solution to these issues by maintaining optimal humidity levels within the aircraft cabin. This helps combat dehydration, improve sleep quality, alleviate fatigue, enhance concentration, and mitigate the symptoms of jet lag. The Humidifier Onboard transforms air travel into a healthier and more pleasant
experience by ensuring a more hydrated and comfortable environment.

Welcome onboard an airplane with a Humidifier Onboard 
 for a good night’s sleep and a restful flight 

What to read next

➔ How low cabin humidity impacts taste, smell, and health 
Say goodbye to dry skin with Humidifier Onboard airplane
The importance of humidity for human health

White paper: Importance of aircraft cabin humidity – from a scientific point of view
➔ Our product Humidifier Onboard
➔ Contact us for more information about optimizing humidity in your aircraft


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