Dehydration can happen in the cold, too
Key takeaways:
- Dehydration is associated with summer heat, but it can happen in the cold. It's especially important to know what to do if you're doing a remote activity, like snow skiing.
- Signs of dehydration include dry mouth, increased thirst, darker urine, fatigue and headache.
- Avoid dehydration by drinking plenty of water and taking breaks. And, have an emergency plan for your outdoor activities.
We associate dehydration – when the body loses more fluids than it takes in – with summer heat. But it can happen in cold temperatures too, says Aminat Ogun, MD, a family medicine doctor at OSF HealthCare. In fact, since fall and winter activities can take you to remote areas (ice skating, skiing or snow shoveling, for example), it’s all the more important to know how to prevent, spot and treat dehydration.
“Early signs of dehydration include dry mouth, increased thirst, darker urine, fatigue and headache,” Dr. Ogun says. “When it’s more severe, it can cause a drop in blood pressure, increased heart rate and confusion. And it can affect kidney function.” Your body temperature could fluctuate, too.
“When we’re cold, we tend to feel less thirsty and drink less water. Our blood vessels constrict to keep the body warm. That pushes blood to the center of our body,” Dr. Ogun explains. “Our kidneys think we have more fluids, so they produce more urine. So you may be losing fluids [by urinating].” Wearing layers of clothes can also cause you to lose fluids by sweating. Older adults are also at a higher risk of becoming dehydrated.
Luckily, avoiding all this isn’t hard. Dr. Ogun says simply: drink water. For men, aim for 15 cups per day. For women, try for 11 cups. Keep a water bottle or a cooler stocked with drinks handy. But avoid excess consumption of sugary, caffeinated drinks like sports drinks, soda and alcohol. Tea, warm soups and low-sugar electrolyte drinks are also OK, Dr. Ogun says. Or, try flavoring your water with lemon. You can even set an alarm on your phone if you need a reminder to drink, and you can track your progress on your phone.
Also, have an overall emergency plan for activities like snow skiing where you’re not near a hospital. Tell someone your plans, pack a first aid kit, keep your phone and GPS charged and know what to do and who to call if someone gets hurt. Dr. Ogun says if someone is feeling woozy, everyone should take a break. Get to a warm place, and get the person some water and a snack.
For most people, drinking the recommended amount of water is important for good health. However, people with heart failure may need to limit their fluid intake based on their health care provider's recommendations. Though rare, it is possible to drink too much water in a short period, leading to dangerously low sodium levels (hyponatremia). Symptoms of drinking too much water include nausea, cramps, swelling and discolored hands and feet, drowsiness, confusion and even seizures. If you’re drinking a lot of water and start to feel unwell, stop drinking and seek medical help.
Learn more
More resources on staying hydrated from OSF HealthCare:
OSF HealthCare blog: Why you should be drinking more water
Infused water recipes
OSF HealthCare library: Dehydration
OSF HealthCare Newsroom: How much water is too much?
OSF HealthCare Newsroom: Sneaky signs you may be dehydrated