How to Stay Hydrated When Crossing a Desert

When you think about a desert, I’d bet that you think blistering heat, rolling sand dunes, camels and unrelenting sunshine. You’d not be wrong, but this doesn’t cover the whole picture. There are many other types of desert on Earth, 5 in total labelled subtropical, coastal, rain shadow, interior, and polar. Yes, polar. Experts typically label a body of land as a desert when it receives no more than 25cm of rainfall each year, and this means that in all deserts there is a shortage of water enough to sustain many plants and other organisms. While not all deserts are hot, they are all dry. This makes hydration a particularly important topic to know about if you are planning on entering, crossing or inhabiting a desert for any length of time. 

There are three main pillars to managing hydration in the desert, and all crucial to consider and prepare for:

• Mineral loss
• Dehydration
• Hyper-hydration

Mineral loss through sweating and urination

When your body heats up, it sweats in order to cool down. But, what many people don’t think about is the minerals that are escaping during this sweat process. Anyone who’s ever taken a spin class knows what sweat tastes like, salt. There are 4 main minerals which the body needs in order to properly function; potassium, calcium, sodium, magnesium. 

Sodium is arguably the most important to replace as you’ll need it most. Sodium has many jobs in your body including regulating fluid balance, maintaining blood pressure at a normal level, and supports your muscles and nerves. Extreme loss of sodium can lead to muscle cramps and nausea, vomiting and dizziness as well as more serious conditions such as comas or even death. So, I’m sure you’d agree it’s crucial to keep those levels maintained. 

Fortunately, there are many ways to ensure you’re replacing your minerals throughout your expedition. Firstly, you should consider the balance of foods that you’re consuming- checking the labels will give you all the info you need, and the right mix of food will mostly keep these mineral balances in check. However, it would be sensible to take supplements for use as and when required. Some good examples would be:

• Rehydration tabs, available from the vitamins section in most supermarkets. Things like Dioralyte.
• Energy drinks- take the powdered kind that can be added to water. Be sure to get a decent one that actually contains the things that you need
• Electrolyte tablets
• Unrefined salt which contains all of the minerals you need. You could pre-fill some large gelatin supplement capsules (available in most sports websites) which will aid with dosing, taste and convenience. It will also prevent spoilage as you can store capsules in smaller boxes, or divide them across your meal bags.

Dehydration

Dehydration really is the condition causes by both water and mineral loss. But it is most commonly associated with lack of water. So I’ll talk mostly about managing water loss in this section, as we’ve already covered mineral loss above.

It goes without saying, if you’re entering or attempting to trek across a desert you’ll need to carry with you all of the water that you’ll need for the entire journey, or have caches of water dropped in advance at key locations. Typically, it’s advised for an average person to take 5litres per day in cooler seasons and up to 10 litres in hotter seasons. But, you will need to work out how much water you’ll need for your specific journey/leg and there are several factors involved in this calculation:

• Time travelling per day, and the amount of effort spent doing so. Consider your mode of transport, driving is easier than camel riding, which is easier than trekking, and so on
• The heat
• Your condition. Are you used to this kind of heat and exertion? If you’ve been living and working in hot climates for a long time, then you might need less than someone jumping straight off a plane from Sweden.

Understanding your body

You body has developed early warning signals that manifest in physical signs and warn us when something is in danger of becoming serious. Consider hunger, thirst, tiredness, anxiety and so on. However, you need to understand your limits very very well. This is why it’s important to work your way up to bigger expeditions, as you need to be exposed to tougher situations in order to ‘expand your dials’, and learn to read your body better and better. For example, most people’s stomachs start rumbling as soon as they miss a routine meal yet we all know that you can last a lot longer without eating before it becomes a real problem. The same goes with thirst, which can be an unreliable indicator for the same reasons. A better gauge would be the colour of your urine, which will get darker and more yellow/golden the more dehydrated you become. However, ultimately there is no true fact for how much water an individual person will need, so you really need to be experiencing and testing yourself in advance to gain as much information as possible about the way your body handles water.

It’s also worth noting that in dry conditions it might actually feel like you’re not sweating much, but sweat will evaporate almost instantly when the temperatures are soaring. 

How to limit your water use in a desert

As with any expedition, resources are limited and must be managed, and the best way is to reduce usage and reduce risk of loss. Aside from drinking, you also need to factor in water used for cooking, which can add 30-50% extra burden to carry. Water should be stored in safe, strong containers to avoid splitting or warping, and where possible store caches of water in separate places to avoid a devastating loss of all your water from a single accident/event. 

You can also limit your usage by managing your requirements. This means pacing your exertion, taking a slower and steadier pace, then speeding up as the days go on. You should also:

• Only travel during the mornings, evenings and night when the temperatures are much lower. Rest during the hottest points of the day
• During rest, seek shade wherever possible
• Make sure that you’ve taken and are using appropriate clothing to shield you from the heat and to keep moisture loss to a minimum.

Hyper-hydration

What is hyper-hydration?

The opposite of Dehydration, is hyperhydration or overhydration. This is when you’ve drank too much water, and not replaced the vital minerals lost through excessive sweating and urination. Be under no illusion, hyper-hydration can be fatal and kills athletes every year in normal conditions (non-desert). So how can you avoid hyper-hydration?

• Keep tabs on your urine colour, it shouldn’t be constantly clear
• Drink little and often. Sipping a few mouthfuls at a time rather than downing 2 litres at every break will ensure your bodies gauges are reacting in real time and you can listen to what you need
• Avoid mineral loss by using supplements and eating the right foods