Breathing in the cold (importance of winter hydration)
By Sarah Willis PhD.
Additional tips to consider for maintaining healthy lungs through the season include finding a humidifier to add moisture to the air you breathe with water bowls near heating sources, to be able to rest and relax in spaces with higher humidity. It is also important to become aware of the air quality which you breathe, as we generally spend more time inside during winter where there can be changes in the air pollution from wood-burning stoves, candles, and fireplaces, which can trigger lung problems. Being ever aware of the signs of dehydration as discussed above, while continuing to practice good hand washing, wearing a mask, and getting vaccinated as needed. Moreover, keeping dry and wearing warm clothing, and avoiding extensive work outside – as we internalize heat when in the cold, which increases risk of hypothermia and frostbite. We need to be extra careful of long exposure to cold temperatures. In addition, keeping an eye on the local air quality, avoiding exposure to smoke and second-hand smoke environments, staying hydrated (as discussed above, though avoiding carbonated beverages) and eating healthy.
We all are aware that wintertime and race season increases the chance for ‘catching a cold’ or developing an illness. In these cases, our respiratory system is often affected and in that our lung health. Let’s quick refresh our respiratory system, which is consists of the nose and nasal cavity, sinuses, mouth, pharynx (throat), larynx (voice box), trachea (windpipe), diaphragm, lungs, bronchial tubes/bronchi, bronchioles, alveoli (air sacs), and pulmonary capillaries surrounding the alveoli. For this article we will focus mainly on the lungs, and the formation of mucus and how it prevents irritants from entering our deep lung tissue.
What is so tricky about the cold air of winter? The cold air can/often causes irritation through inflamed airways eliciting sensations of coughing, wheezing, and shortness of breath. Cold air has lower moisture than warm air, it is less humid; therefore, the body responds by producing more mucus due to the dry and irritated airways.
Our lungs have a thin, humid/moist lining of mucus (called the mucosal lining). It is a thin film of mucus that has been secreted by goblet cells, which are scattered along tiny hair-like cilia lining the airways to create a kind of ‘trap’ and move particles out of the lungs. It continues from there moving out of the lungs and to the throat where these particles can be coughed up or swallowed. The role of mucus is to protect the lungs from infection while keeping the respiratory system running and prevent irritation (trap particles and stop them from reaching deeper lung tissues), while also being a kind of ‘vehicle’ to help the body expel irritants through coughing.
The goal is to keep our airways hydrated and to moisturize the mucosal lining. We now understand that hydration becomes infinitely more important when exposed to dry and cold environments. Drinking water helps to maintain the moisture in the lining of our lungs. Whereas, when we are dehydrated, the lining becomes thicker and gets sticky, which impairs our lung function and makes breathing difficult. Staying hydrated is vital to prevent problems and keep airways moist and reduce irritation.
If dehydration is bad for our lung health, then we should key in on the signs and symptoms of dehydration. Here are some things that could bring a dehydration ‘caution flag’: exhaustion, muscle fatigue, cramps, lack of coordination, dark yellow urine.
Let’s focus on why hydration is so important for breathing. As mentioned above, colder weather brings with it lower levels of humidity. In addition, the air is drier and therefore, the lungs need to work overtime. The work of breathing (respiration) results in water loss, as the air we inhale is humidified by the lungs and then the added moisture is exhaled as water vapor with each breath. So, the more work the body does (in this case for the effort of breathing, but this also applies as a general concept), the more hydration it needs to compensate for the greater water loss. In fact, the lungs can exhale greater than 1 liter of water vapor each day, indicating that we lose a lot of water through our lungs especially in winter weather conditions we face as XC skiers (dry and cold climates).
To clarify how hydration helps our breathing, drinking water (for example) moistens the thin mucus lining of our lungs making it easier to clear the airways. Hydration also reduces irritations and keeps mucus membranes healthy, which can reduce the risk of infections. Furthermore, hydration helps to remove toxins out of our system.
So, how do we stay hydrated? We will start by highlighting to drink plenty of water, tea, or decaffeinated coffee; followed by making sure to drink before (pre-hydration) and after exercise; eating more fruits and vegetables for higher water content and antioxidants; considering adding flavor and excitement to water through lemons, oranges, limes.
Another unique and helpful consideration is to use the nose for inhaling, as there is then greater time to warm up the air prior to traveling to our lungs and less water loss.
Taking note of these insights will help to prevent illnesses such as bronchitis, pneumonia, respiratory infections, etc. Of importance, exercise induced bronchoconstriction – a common type of asthma caused by high-intensity exercise or exercise in a cold environment (or both, as often in XC skiers), triggers the inflammatory response that induces airway constriction and difficulty breathing (during or after exercise). This demonstrates the importance of this topic for us as we are in ski season now.
Extra caution should be taken when there is more mucus developing, indicating dehydration with more irritation and dry airways. Hydrating the lungs through liquids as well as eating more lemons, ginger, and garlic will also be helpful. Honey is thought to have sweetness that triggers the salivary glands to produce more saliva and lubricate the airways to ease coughing and reduce inflammation within the bronchial tubes. All of this helps break up the mucus which is what is making it hard to breathe in the first place. Staying hydrated is important for regulation of our blood pressure, temperature, nutrient transport, protecting organs and joints, removing waste, maintaining proper cognitive function, as well as in the work of breathing. Cheers (with an ideally warm watery drink) to a hydrated season ahead keeping your lungs functioning properly and illness away!