High Altitude Dehydration is Real – Here’s How to Prevent It

High-altitude dehydration is one of the most common challenges you may experience, especially if you’re training, racing, or being very active. Drinking enough water can mean the difference between feeling good on the mountain and feeling just blah, or even really bad. And we definitely want you to feel good out there! So, get the facts about high altitude dehydration, plus tips for keeping it at bay so you can shred all day.


Does High Altitude Speed Up Dehydration?

It’s pretty well-known that dehydration is one of the potential effects of high altitude. If you’re wondering what is considered “high” elevation—benchmarks vary by source but you can use the following reference points:

  • High altitude – 8,000 to 12,000 feet above sea level
  • Very high altitude – 12,000 to 18,000 feet
  • Extremely high altitude – 18,000+ feet

Depending on your body, you may become more prone to dehydration starting at elevations of 5,000 feet. 

So, why does high altitude cause dehydration? You’re more likely to get dehydrated exercising at high elevation than when you’re at sea level due to a few combined factors: 

Faster Rate of Respiration 

With less oxygen at high altitudes, your breathing becomes faster and shallower, contributing to increased water loss. Not to mention if you’re skiing, snowboarding, snowshoeing, or mountain biking at high altitudes you might already be breathing harder than usual.

Lower Humidity 

The higher the elevation, the dryer the air (and the lower the air pressure). You feel it in your eyes, nose, skin, and even your hair. This also means moisture evaporates more quickly from your skin, which could trick you into thinking you’re not losing water through sweat, when in fact you definitely are. 

Increased Urine Production 

High altitude can also cause you to urinate more, increasing the risk of dehydration. The scientific name for this is high-altitude diuresis. In short, your kidneys react to the drier climes of high elevation by releasing more of certain hormones and less of others. While this helps regulate the thickness of your blood and its ability to carry oxygen in these harsher conditions, it also causes you to pee more often. 

Decreased Thirst

Even though your body loses fluids faster at altitude, you’re less likely to crave the water you need to perform well. Your risk is even higher in cold temperatures, which can further reduce your impulse to drink. That’s why it’s so important to drink lots of water when you’re exercising in the mountains—you can’t always rely on thirst to be your guide.

Dehydration Symptoms to Look Out For

We talk a lot about dehydration symptoms here at CamelBak—water is a basic human need, after all. The condition can be serious or even life-threatening, so recognizing the onset of dehydration ASAP is super important. 

Some early warning signs of dehydration include:  

  • Thirst
  • Dry mouth and tongue
  • Dizziness 
  • Weakness or fatigue
  • Headaches
  • Confusion 
  • Crankiness
  • Dark-coloured urine

Keep an eye on yourself and your friends when you’re hiking, skiing, biking or doing other activities at great heights.

How Do You Stay Hydrated at High Altitude?

Now that you understand the connection between high altitude and hydration, what can you do about it? Here are our best hydration tips for sports and outdoor fun when you’re high above sea level:


The best way to beat high-altitude dehydration is to stay ahead of it. Drink plenty of water in the days and hours before heading to a high-altitude destination. Whether you’re sitting in the car, aeroplane, or on your way to the trailhead, drinking water should be a part of your preparation for excursions at elevation.

Start Slow 

Ease into your activity. Especially if you’re not used to high altitude, your body will have to work harder in these conditions. If possible, give your body time to acclimate and rest before jumping into a race or intense exercise. This can also mean ascending gradually versus going from zero to 10,000 feet in a single day. 

Consume Hydrating Foods

Besides drinking water, you can support hydration by eating foods with a high water content like apples, cucumbers, melons, strawberries, broccoli, celery, zucchini, and lettuce. These foods won’t replace your necessary water intake—rather they supplement it.  

Moderate Caffeine and Alcohol 

Alcohol and caffeine are diuretics, which means they promote increased urine production. Given that you’ll already be going for more “bio breaks” at high altitude, you don’t want to exacerbate that. Try to focus on water and other hydrating beverages, consume in moderation, or save your cocktail or craft beer for an apres-ski reward.  

Drink Consistently Throughout the Day

Make drinking water at high altitude an ongoing thing. Plan for hydration breaks throughout the day and bring a reusable water bottle or hydration bladder with you so that water is always within reach. CamelBak has a full line of hydration packs for snow and winter sports, designed to prevent your water from freezing and keep you sipping throughout the day.  

Balance with Electrolytes

People often wonder about Pedialyte, sports drinks, electrolyte drinks or electrolyte powder mixes for staying hydrated in high altitude. Electrolyte balance is critical for peak performance and avoiding dehydration. This is especially true in high altitudes, as you need to replace the salt your body is losing via sweat and increased respiration and urination. 

How Much Water Should I Drink at High Altitude? 

How much water do you need to drink to avoid dehydration or altitude sickness? If you’re trying to avoid high-altitude dehydration, then you’re probably asking this very question.

According to the High Altitude Doctor (formerly Institute for Altitude Medicine) you need to drink an additional 1 – 1.5 liters of water per day when in high altitude. If you go too overboard on drinking water, it could cause a sodium imbalance and lead to hyponatremia, which is not fun. As a good rule of thumb, check your urine to assess your hydration level during high-altitude activities. If it’s clear or light-colored, you’re most likely hydrated enough. If it’s dark, that’s an indication you need to drink more water. 

Related Blog Posts