By: Dr. Magdy Badran
Dry air has a low relative humidity. When the relative humidity drops below about 40% the air feels dry to the skin. Dry air has the ability to worsen a wide range of health issues, from respiratory conditions and skin problems to nosebleeds, dry eyes, sore throats, and more.
Because our bodies are comprised of approximately 70% water, it should come as no surprise that exposure to dry air can lead to dehydration. When you’re exposed to dry air, the air will attempt to draw moisture from anything it can, including the human body. The moisture in and on your skin will evaporate, as will the moisture in your lungs, eyes, nose and body.
Spending long periods in very dry indoor surroundings can deplete your body’s fluid levels and make the urine much more concentrated. Urine concentration is one biomarker of dehydration. Dehydration is a serious issue that can prevent the proper digestion and absorption of nutrients.
Dry Air and Immunity
Dry air may increase your risk of getting the flu or even pneumonia. In reality, having some humidity is healthy in the autumn and winter. A recent review of 37 different studies revealed that humidity directly relates to childhood asthma and other pediatric allergic diseases. In Japan, emergency visits for childhood asthma increased when humidity levels had a rapid decrease. The same thing happened in Western Europe. Over there, children’s asthma symptoms spiked during the lowest monthly average of relative humidity. Not surprisingly, low humidity was also connected to eczema in Taiwanese schoolchildren.
Dry Air and Sinus Health
Adults breathe approximately 23,000 times a day. The air we are breathing is important in making sure our bodies’ function effectively to ward off illness and infection. Prolonged exposure to low humidity levels can cause the mucous membrane that lines your throat and nose to dry out and become compromised.
Sinuses that are dry are 50% more likely to attract sinusitis-causing bacteria than moist sinuses. Humidity levels between 40%-50% are the healthiest for the sinuses. Problems with mucus drainage may also occur if airborne allergens in the air are inhaled into the sinus through the nasal cavities.
Dry air can be a direct result of cold weather and indoor forced-air heating. This can lead to frequent or chronic sinusitis. Dry air affects the sinuses because it damages the cilia that filter out the bacteria and debris in the mucus membrane lining the nasal and sinus cavities.
Dry Air Effects on The Respiratory System
A dry upper respiratory tract makes it more difficult to breathe comfortably. Having some moisture in the air helps us breathe easier and makes it harder for airborne infections to migrate. Without the moisture in the air, you might even be tempted to crank up the heat even higher—which only exacerbates the problem.
Cold air is often dry air. Dry air can irritate the airways of people with lung diseases. This can lead to wheezing, coughing and shortness of breath.
Asthma symptoms, especially spasms, can be worsened by cold, dry air. When you’re in a very low humidity environment, the fluid that hydrates your bronchial tubes can quickly evaporate. This can leave the airways vulnerable to irritation. This is especially likely during winter months.
In addition to asthma, the symptoms of bronchitis other respiratory illnesses can also worsen if you spend too much time in an environment with overly dry air.
A sore throat is a painful, dry, or scratchy feeling in the throat. Pain in the throat is one of the most common symptoms, which accounts for more than 2% of all adult primary care visits each year. While some people automatically assume a respiratory infection is to blame for their sore throat, the actual culprit may be the dry air.
Prolonged exposure to excessively dry air absorbs moisture from the delicate mucus membranes coating the throat. Exposure to dry air causes the saliva in the throat to literally evaporate, making it feel rough and scratchy.
Many people run space heaters in the winter in addition to forced air heating in the home, which compounds the problem of dry air. If you’ve ever woken up in the night and found it difficult to swallow, it may not surprise you to learn that dry air can cause pain and inflammation in your throat.
Dry Air Effect on The Eyes
When we are exposed to a dry atmosphere, our eyes become dry as moisture is drawn from the film that covers them. This “tear film” forms a protective barrier, covering the surface of the cornea. It serves as a defense against microbial infection, supplies essential oxygen and nutrients to the cornea, removes waste particles and provides the moist environment needed for clear vision and healthy eyes. It protects the cornea from damage.
When our precorneal tear film dries, it can lead to a soreness or burning sensation of the eye, blurred vision and an increased susceptibility to eye infections. Contact lens wearers are particularly at risk from dry eyes as contact lenses will increase the rate of evaporation from the tear film.
Dry Air and Dermatitis
Cold air, wind and a decrease in humidity can all dry out skin. That loss of moisture can cause eczema to flare. You may find that eczema flare-ups occur more frequently or get worse in the winter. Dry indoor air, especially air-conditioned environments, can lead to rough, dry skin.
Desiccated and cracked skin loses its protective, physical barrier function. Microbes, allergens and harmful chemicals can penetrate the cracks, triggering infections, allergic and toxic skin diseases.
Air that’s too dry can also decrease your skin’s elasticity. Dry air can also weaken your skin’s barrier function. As a result, when you come into contact with allergens or irritants, your skin may be more easily damaged.
Dry air is the most common cause of nosebleeds. Dry air can cause the nasal membrane to dry out and become crusty or cracked and more likely to bleed when rubbed or picked or when blowing your nose. While nosebleeds are more common in winter months when homes and offices are heated, they can occur in any season when indoor air humidity is low.
Dry Air and Allergic Fatigue
Fatigue is an all-too-common problem that millions of people experience. While some people assume their lack of energy is caused by not getting enough sleep, the underlying cause may actually be associated with dry air.
Allergic fatigue is a condition characterized by a sudden drop in energy levels associated with an allergic reaction to one or more allergens. Men and women of all ages experience allergies. After going for a walk around the neighborhood, your nose may begin to run, you may develop a headache, red eyes, and a general feeling of being tired. There must be some type of trigger to stimulate the body’s reaction. This can be pollen, dust mites, pet dander or mold spores. The less time you spend outside during a day with, the less likely you are to experience an allergy attack. Dry air doesn’t effectively slow down the spread of allergens like moist, humid air; therefore, exposure increases the risk of allergic fatigue.
Spending prolonged periods in very dry indoor air may increase your stress level. Those who worked in the buildings with drier air had heart rates that indicated a stress response. They also reported poorer sleep.
Tips to Tackle Dry Indoor Air
Use a humidifier to moisten the air, shorter showers and warm (instead of scalding hot) showers. Use skin moisturizers after bathing and hand washing. Use lip balm to prevent dry, cracked lips. Stay well hydrated by drinking plenty of water all year long. Help keep your nasal passageways moist by using salt water (saline) drops or rubbing a little petroleum jelly into each nostril gently with a cotton swab.
Removing irritants is important because continued exposure can cause mild discomfort and even breathing problems. Seal your home, prevent the cold, dry air outside from paying you an unwelcome visit and close any air leaks in doors.
Thanks a lot.
Dr Magdy Badran