The Truth: Does Ice Make You More Dehydrated?

January 5, 2026 •

4 min read

According to a survey, 79% of Americans prefer cold water, particularly on hot days or after exercise. This preference exists despite the persistent misconception that consuming ice can make you more dehydrated, a belief tied to the body's negligible energy expenditure to warm the liquid.

Quick Summary

No, consuming ice or cold water does not cause dehydration; it contributes to your total fluid intake. While the body expends energy to warm it, this process is minimal and has no negative effect on hydration levels. Optimal hydration depends more on consistent fluid intake and listening to your body's cues.

Key Points

Debunking the Myth: Consuming ice or cold water does not cause dehydration; it contributes to your overall fluid intake like any other water source.
Body Temperature Regulation: The body expends a negligible amount of energy to warm cold water, and this process does not negatively impact hydration.
Encourages Intake: Cold water can be more palatable and refreshing, which may encourage you to drink more, especially in hot weather or during exercise.
Inefficient Hydration Source: Eating ice is a less efficient way to hydrate compared to drinking water directly because you consume a smaller total volume of fluid.
Monitor Hydration Status: Pay attention to thirst cues and urine color for accurate hydration monitoring, as relying on water temperature alone is unreliable.
Individual Sensitivity: Some people may experience minor discomfort, like headaches or stomach cramps, from very cold water due to personal sensitivity, but this is not dehydration.

Debunking the Dehydration Myth

The idea that ice makes you more dehydrated is a widespread myth with no scientific basis. The misconception often stems from two core misunderstandings: the body's energy use to heat cold water and the less efficient nature of eating ice versus drinking it. In reality, cold water is equally effective as room-temperature water for hydration.

The Science of Thermoregulation

Your body's thermoregulation system, primarily controlled by the hypothalamus, is incredibly efficient. When you consume cold water, your body uses a very small, insignificant amount of energy to bring the fluid up to its core temperature. This energy expenditure does not deplete your water stores or cause dehydration. Furthermore, in hot environments or during exercise, drinking cold water can actually be more beneficial. The cool temperature helps lower core body temperature, which can reduce the stress on your cardiovascular system and make you feel more refreshed, encouraging you to drink more and stay hydrated.

Understanding the Intake Difference: Ice vs. Water

While consuming ice can help you cool down and provides a temporary feeling of relief, it is not the most efficient way to rehydrate. When you drink a glass of water, your body absorbs that fluid directly. When you chew or suck on ice, the melting process delivers the water in a smaller, slower stream. For this reason, you would need to consume a large amount of ice to get the same hydrating effect as a standard glass of water. Frequent cravings for ice might also signal an underlying issue like iron deficiency anemia (a condition called pagophagia) and are not related to a person's hydration status.

Factors That Actually Affect Hydration

Environment and activity level: You lose more fluid through sweat in hot, humid weather or during intense physical activity. This is when you should be most proactive about rehydration.
Thirst is an imperfect signal: By the time you feel thirsty, you may already be slightly dehydrated. It is important to drink fluids consistently throughout the day, not just when you feel parched. This is especially true for older adults, whose thirst sensation can weaken.
Diet: Consuming water-rich fruits and vegetables, like watermelon and cucumbers, contributes significantly to your daily fluid intake.
Urine color: A simple and effective indicator of hydration status. Pale yellow urine suggests you are well-hydrated, while darker urine indicates a need for more fluids.
Health conditions: Some medical conditions, and even certain medications, can impact your hydration needs and how your body processes fluids.

Comparison of Water Temperatures and Their Effects


Feature	Cold/Iced Water	Room Temperature Water	Warm/Hot Water
Absorption Rate	Can be slightly slower to absorb than room temperature water, but the difference is insignificant.	Absorbed most quickly by the body for effective hydration.	Absorbed slightly slower than room temperature water.
Effect on Body Temp	More effective at cooling the body down, especially during exercise or in hot weather.	Has a neutral effect on body temperature.	Can increase feelings of comfort and warmth on a cold day.
Palatability	Often preferred for its refreshing feeling, which can encourage higher fluid intake.	Can feel less satisfying than chilled water when overheated.	May feel less satisfying to drink large quantities compared to cooler water.
Potential Discomfort	May aggravate symptoms for people with specific conditions like achalasia or migraine.	Generally has no associated digestive discomfort.	Can ease digestion for some, but may feel unpleasant when overheated.

Potential Issues and Considerations

While drinking cold or iced water is perfectly safe for most people, some may experience minor side effects. For example, individuals with a sensitive digestive system may find very cold water causes stomach cramps. Similarly, some people who experience migraines report that drinking ice-cold water can trigger a headache. However, these are personal sensitivities and not signs of dehydration. For the vast majority, the temperature of their water has no negative impact on their hydration status.

Conclusion: The Final Word on Ice and Hydration

To definitively answer the question, no, ice does not make you more dehydrated. The persistent myth is not supported by scientific evidence. Your body efficiently processes water at any temperature to maintain hydration. In fact, for many, the refreshing nature of cold water can encourage them to drink more and, therefore, stay better hydrated. The key takeaway is to focus on consistently consuming fluids throughout the day and using your body’s signals and urine color as a guide, regardless of the water's temperature. For those interested in further reading, the National Institutes of Health provide in-depth information on thermoregulation and hydration(https://www.ncbi.nlm.nih.gov/books/NBK200975/).

Frequently Asked Questions

No, this is a myth. While your body does use a tiny amount of energy to warm cold water, it does not expend or lose more water in the process. The impact on your overall hydration is insignificant.

Yes, eating ice provides some hydration because it is frozen water. However, it is a much less efficient way to rehydrate than drinking water directly, as the volume of water from ice cubes is relatively small.

For most people, no. Some individuals with sensitive digestive systems, or conditions like achalasia, may experience discomfort, but there is no scientific evidence that cold water harms digestion for the general population.

Studies suggest that slightly cool water (around 16°C or 60.8°F) may be optimal, as it is palatable enough to encourage more drinking while also aiding in core temperature reduction.

Some research indicates that drinking ice-cold water can trigger headaches, particularly in individuals with a history of migraines. This is a personal sensitivity, not a universal effect.

Traditional practices, such as in Ayurveda, suggest that cold water can disrupt digestion by 'dampening the fire,' or Agni. However, these beliefs are not supported by Western science.

Some research suggests that drinking cold water can give your metabolism a slight boost as your body expends energy to warm it. However, this effect is minimal and not a significant weight-loss strategy on its own.