Dehydration can happen just as easily in colder weather as it can during the summer months. It is a leading cause of injury for Soldiers. We often don’t feel as thirsty as we do in the summer and we don’t think we are sweating as much, which can be a false perception. According to the Mayo Clinic, we can become dehydrated in the cold from sweating, breathing, and from increased urine production. Yet, fewer people recognize the signs of dehydration in the winter, so it may be even more of a risk during the winter months.
Hydration assessment during cold-weather
We must hydrate even when we are not thirsty. Note that actual fluid requirements are dependent upon the level of physical work performed, the temperature and what you are wearing and carrying. According to one study published by The National Center for Biotechnology Information, our body’s thirst response decreases by 40% in the winter time. This is due to blood vessels constricting when cold weather hits, which ultimately helps for blood to flow to the core and conserve heat. Further, fluids carry nutrients to your cells, flush bacteria from your bladder, and prevent constipation. Drinking plenty of fluids in the cold weather is essential to providing fuel and energy to body parts to help facilitate heat production.
The Importance of overall Hydration
Water comprises about 60% of our body weight and is critical for life. Our body uses water in all its cells, organs, and tissues to help regulate its temperature and maintain other bodily functions. The average adult loses 1½ to 2L of water each day. Being in a cold-weather climate can add to this water loss through the increased excretion by the kidneys, perspiration, and evaporation from the lungs (the breath you see on a cold day). It’s important to rehydrate by drinking fluids and eating foods with high water content.
Drink Plenty of Fluids
Although most doctors do not recommend a one size fits all approach for water consumption, most people are fine with drinking to thirst (around 30-60 oz. per day). According to the U.S. Army Research Institute of Environmental Medicine, Soldiers should drink at least two to six canteens of water each day. Water-rich foods, such as fruits and vegetables, are also a good source of water. Proper hydration is especially important in cold weather as dehydration negatively affects the body's resistance to cold weather, increasing the chance for cold weather injuries.
Prevention is Best! How to Prevent Dehydration
You can prevent dehydration from becoming severe by taking the steps below.
- Make sure you have a water source available with you at all times.
- Drinking plenty of fluids before, during and after exercise is important. Match your drink to the duration of your exercise or training. Electrolytes and carbohydrates are important after longer exercise or training events.
- Monitor symptoms closely and hydrate at the first signs of dehydration. For those who are sick, hydrating at the first sign of diarrhea, vomiting, or fever is crucial.
- Eat plenty of fruits. Winter fruits are excellent sources of water.
- Wear the right clothing to help reduce water loss through sweat.
- Adding Layers to your clothing is a good idea in those cold winter months. This will allow you to adjust your clothing to match the temperature and your activity level on an as-needed basis.
People who exercise outside in extreme weather conditions are at higher risk for dehydration, such as endurance athletes and those training in the military. Extra weight from supplies and gear can accelerate dehydration. Prevention is key when it comes to dehydration. By fueling up with the right foods and drinks, and wearing the right clothing, you can dramatically reduce your risk for dehydration and help stay hydrated during those colder months.
Resources: https://www.mayoclinic.org, https://www.ncbi.nlm.nih.gov and https://www.army.mil