Nutrition Diet: What is the most hydrating drink on a plane?

October 8, 2025 •

4 min read

The humidity in an airplane cabin can drop to below 20%, drier than many deserts on Earth. For this reason, knowing what is the most hydrating drink on a plane is crucial for a comfortable flight and a refreshed arrival.

Quick Summary

The most effective drink to combat dehydration on a flight is plain water, but options like electrolyte mixes and herbal tea can provide added benefits. Avoid alcohol, caffeine, and sugary sodas, as they can accelerate fluid loss due to the low cabin humidity and pressure.

Key Points

Plain Water is Best: Water is the most hydrating drink on a plane, so drink plenty of it before and during your flight to combat dry cabin air.
Consider Electrolyte Supplements: For long-haul flights, adding an electrolyte powder or tablet to your water can more effectively replenish essential minerals lost due to dehydration.
Avoid Alcohol and Caffeine: Both alcohol and caffeine are diuretics that cause your body to lose more fluid, worsening dehydration and fatigue at high altitudes.
Opt for Safe Alternatives: If you want a flavored beverage, choose club soda, herbal tea, or coconut water instead of sugary sodas or juices.
Use a Refillable Bottle: Bring an empty reusable water bottle to fill after going through security. This ensures you have a continuous supply and don't have to wait for the beverage cart.
Be Wary of Airplane Tap Water: Avoid coffee or tea made with onboard tap water due to potential bacterial contamination, and stick to sealed bottled water instead.

Why Flying Causes Dehydration

Dehydration is a common and often underestimated issue for air travelers. Several factors contribute to the significant fluid loss experienced in the air, with the cabin environment playing the largest role.

Low Cabin Humidity

The air circulating inside an airplane cabin is notably low in humidity, often ranging from just 10% to 20%. This dry air draws moisture from your body, particularly from your skin, eyes, and throat, causing it to evaporate much faster than it would at ground level.

Reduced Air Pressure

Even though cabins are pressurized, the air pressure is still lower than what your body is accustomed to on the ground. This difference causes fluids to move out of your body more quickly through normal processes like breathing. Over a long flight, this seemingly small fluid loss accumulates, increasing your risk of dehydration.

In-Flight Drink and Snack Choices

Many popular in-flight beverage and snack choices work against your hydration efforts. Drinks with caffeine and alcohol act as diuretics, causing increased urination and fluid loss. High-sodium snacks, also common on flights, can further exacerbate the problem by drawing water from your cells.

The #1 Choice: Plain Water

When considering what is the most hydrating drink on a plane, plain water is the undisputed champion. Its simplicity and purity mean it is absorbed efficiently by the body without any dehydrating effects from sugar, caffeine, or alcohol. For optimal hydration, it is recommended to drink about 8 ounces (240 ml) of water for every hour of flying. A key strategy is to bring an empty reusable water bottle through security and fill it up before boarding to ensure you have a constant, ample supply.

Boosting Hydration with Electrolytes

While water is the best baseline, a long-haul flight can also deplete essential electrolytes like potassium and magnesium, which help regulate fluid balance.

Electrolyte drink powders or tablets: These can be easily mixed with water to create a hydrating beverage that replenishes lost minerals. Look for options with low or no added sugar to maximize the benefit.
Coconut water: This is a naturally occurring, electrolyte-rich beverage that can help you rehydrate effectively. It contains potassium and magnesium, making it a great natural alternative to commercial sports drinks.

Other Smart In-Flight Drinks

For those who prefer some variety, several other options can support your hydration goals.

Herbal tea: Caffeine-free herbal teas like chamomile or peppermint are an excellent warm beverage choice. They provide hydration and can have soothing effects, aiding digestion or relaxation. However, be mindful that some sources recommend avoiding hot drinks made with airplane tap water due to potential bacterial contamination.
Fruit-infused water: Adding slices of fruit like lemon, lime, or cucumber to your water can add a subtle flavor without extra calories or sugar. This is a great way to encourage more water consumption.
Club soda or seltzer: If you crave a bubbly drink, club soda or unflavored seltzer is a better choice than sugary soda. It provides refreshing fizziness without the dehydrating sugar.

The Worst Drinks for In-Flight Hydration

To maximize your hydration and overall well-being, it's best to avoid certain beverages. These drinks actively work against your body's fluid balance at high altitude.

Alcohol: This is a powerful diuretic that will cause your body to lose more fluid than it takes in. The effects of alcohol are also more potent at high altitudes, so even a single drink can lead to faster dehydration and worse jet lag.
Coffee and Caffeinated Tea: Caffeine is a diuretic that increases the need to urinate, contributing to fluid loss. It can also interfere with sleep patterns, which are already disrupted by travel.
Sugary Sodas and Juices: The high sugar content in these drinks can cause energy crashes and contribute to dehydration. Many people also find that carbonated drinks can cause uncomfortable bloating and gas due to cabin pressure.
Excessive Tomato Juice: While a popular airplane drink, it's often high in sodium, which can contribute to bloating and dehydration. If you enjoy the flavor, consider a lower-sodium version.

Comparison of In-Flight Drinks


Drink	Hydration Level	Benefits	Drawbacks
Plain Water	Excellent	Optimal absorption, no additives, free on flights	Can be plain, relies on airplane water source if not bottled
Electrolyte Mixes	Excellent	Replaces lost minerals, can boost energy	Can contain added sugar or artificial sweeteners
Coconut Water	Excellent	Natural electrolytes, refreshing taste	May not be available on all flights
Herbal Tea	Good	Relaxing, soothing, warm comfort	Potential contamination from airplane water source
Seltzer/Club Soda	Good	Flavorful alternative to sugary sodas	Potential for bloating and gas due to carbonation
Alcohol	Poor	Can be relaxing in small amounts	Diuretic, potent at high altitude, worsens dehydration
Caffeinated Drinks	Poor	Provides temporary energy boost	Diuretic, disturbs sleep patterns, risk from tap water
Sugary Sodas	Poor	Satisfies sweet cravings	High in sugar, causes bloating, dehydrating

Conclusion

For any flight, the best strategy is to make plain water your primary beverage. Water is the most direct and effective way to counteract the dehydrating effects of low cabin humidity and pressure. For longer journeys, supplementing with an electrolyte mix can be a game-changer for maintaining fluid balance and energy levels. By avoiding dehydrating drinks like alcohol and caffeine and planning your hydration strategy, you can arrive at your destination feeling refreshed and ready to go. To ensure safety, always opt for bottled water over airplane tap water for hot or cold drinks.

Learn more about staying hydrated while traveling from reliable sources such as Abbott Nutrition News.

Frequently Asked Questions

People get dehydrated on planes due to the low humidity in the cabin, which is drier than a desert. This causes moisture to evaporate faster from the body, leading to significant fluid loss over the course of a flight.

Experts recommend drinking at least 8 ounces (240 ml) of water for every hour you are in the air. Carrying a reusable water bottle and sipping regularly is the best way to maintain consistent hydration.

While popular, tomato juice can be high in sodium, which may contribute to dehydration and bloating. Coconut water is a better natural alternative with more beneficial electrolytes.

For most people, water is sufficient, but electrolyte drinks can be more beneficial on very long flights or for those prone to dehydration, as they help replenish lost minerals more efficiently.

Alcohol acts as a diuretic, causing increased fluid loss and accelerating dehydration. Its effects are also more pronounced at high altitudes, which can worsen jet lag and overall discomfort.

It is best to avoid coffee and tea. Caffeine is a diuretic, and both hot drinks are often made from airplane tap water, which studies have shown can have questionable cleanliness.

To add flavor, you can bring a small pack of fruit-infusion sachets or add a squeeze of lemon or lime from the beverage cart to your water. Seltzer or club soda are also good alternatives for a bubbly sensation.