Does Drinking Water Have Any Calories? The Definitive Answer

October 30, 2025 •

3 min read

Over half of the human body is made up of water, a fundamental component for nearly every bodily function. For those monitoring their intake, a frequent question arises: does drinking water have any calories? The straightforward and scientifically-backed answer is no, plain water contains zero calories.

Quick Summary

Pure water is entirely calorie-free because it contains no macronutrients like carbohydrates, fats, or proteins. Calories are a unit of energy, and water does not provide metabolic energy, making it an ideal beverage for hydration and weight management.

Key Points

Zero Calories: Plain tap, bottled, and sparkling water contain zero calories because they are free of macronutrients like carbohydrates, proteins, and fats.
Energy Source: Calories are a unit of energy, and water does not provide metabolic energy for the body.
Weight Management: Replacing high-calorie beverages with water is an effective strategy for weight loss and management.
Hydration Benefits: Proper hydration, facilitated by drinking water, supports metabolism, aids digestion, and can suppress appetite.
Check Labels: Flavored or enhanced waters may contain added sugars or sweeteners that contribute calories, so it's important to read the nutrition label.

The Science of Calories and Why Water Has None

To understand why water is calorie-free, it's essential to first define what a calorie is. A calorie is simply a unit of energy derived from macronutrients—carbohydrates, proteins, and fats—which your body uses for fuel. In food science, calories are measured by burning a sample in a device called a bomb calorimeter and measuring the heat produced. Since water cannot be burned for energy in this process, it yields zero calories. The molecule of water ($H_2O$) is composed of hydrogen and oxygen, and its chemical bonds do not provide the body with usable energy in the way that the complex bonds of food molecules do.

The Role of Water in Energy Metabolism

While water provides no energy itself, it is a crucial component of the metabolic processes that extract energy from the food you eat. Water acts as a solvent for nutrients and facilitates chemical reactions, including the process of lipolysis, where stored fats are broken down for energy. Without adequate hydration, these metabolic functions become less efficient, which is why dehydration can lead to fatigue.

Types of Water and Their Calorie Content

Not all water is created equal when it comes to calories. While plain tap and bottled water are universally calorie-free, variations and additives can change this nutritional profile.

Flavored Waters

Artificially Sweetened: Many flavored or 'enhanced' water products on the market are sweetened with non-caloric sweeteners like stevia or sucralose, which provides flavor without adding calories. These are generally safe for those watching their caloric intake.
Sugary Additions: Waters flavored with fruit juice, syrups, or sugar will contain calories. The calorie count will depend on the amount and type of sweetener used. Always check the nutrition label on these products.

Sparkling Water

Plain carbonated water, or seltzer, is made by infusing water with carbon dioxide gas. This process adds no calories or sugar, so plain sparkling water remains calorie-free, just like its still counterpart. However, be mindful of sparkling drinks that contain added fruit juice or artificial sweeteners, which may contain calories.

Water, Weight Management, and Satiety

For those on a weight management journey, water's zero-calorie nature is a significant advantage. Replacing high-calorie, sugary beverages like soda or juice with water can drastically reduce overall caloric intake. Furthermore, drinking water, especially before meals, can contribute to feelings of fullness and potentially lead to consuming fewer calories during the meal.

How Water Affects Appetite

Sometimes, the body's signal for thirst is misinterpreted as a signal for hunger. By drinking a glass of water when you feel hungry, you can determine if your body is truly craving food or if it just needs hydration. The volume of water also helps to temporarily fill the stomach, sending signals of fullness to the brain.

The Difference Between Plain and Flavored Water


Feature	Plain Tap/Bottled Water	Flavored Water (e.g., fruit juice added)
Calorie Content	Zero calories	Variable, depending on additives. Can range from negligible to moderate.
Energy Source	Provides no metabolic energy	Provides energy if it contains carbohydrates or sugars.
Nutritional Value	May contain trace minerals like calcium and magnesium.	Varies greatly; may include vitamins or sugars from additives.
Effect on Weight	Excellent for weight management as a zero-calorie hydrator.	Can contribute to weight gain if sweetened with sugars.
Digestion	Essential for proper digestion and metabolic processes.	May provide hydration but can be less beneficial if containing excess sugar.

The Verdict on Water and Calories

So, does drinking water have any calories? In its purest form, absolutely not. The caloric value of any beverage comes from the presence of macronutrients like sugar, protein, and fat, all of which are absent in plain water. This makes water the perfect, zero-calorie choice for staying hydrated and supporting your body's essential functions, including those related to weight management. Always check the labels on bottled, flavored, or enhanced water products, as additives can introduce calories where none existed before. For pure, guilt-free hydration, plain water is the clear and calorie-free champion.

Visit the CDC for more information on the health benefits of choosing water

Frequently Asked Questions

Water is a simple compound of hydrogen and oxygen ($H_2O$) and does not contain the carbohydrates, proteins, or fats that your body breaks down for energy. Calories are a measure of the energy contained in food, and water has no chemical energy that your body can use as fuel.

No, plain tap water and plain bottled water both contain zero calories. The slight mineral variations between different sources are not a source of calories.

Plain sparkling water and seltzer are calorie-free, as they are simply water infused with carbon dioxide gas. However, if the product contains added flavors, sugars, or juices, it will likely contain calories, so it's essential to check the label.

Drinking cold water can cause your body to expend a very tiny amount of energy to warm it up to body temperature. However, this effect is negligible—only about 8 calories for a glass—and is not an effective weight loss strategy.

Yes, indirectly. Drinking water can promote weight loss by increasing feelings of fullness before meals, which may lead to a lower calorie intake. Replacing sugary drinks with water is also a simple way to reduce your overall calorie consumption.

The calorie difference is substantial. Water has zero calories, while common beverages like soda, juice, and sweetened coffee contain a significant number of liquid calories from sugar, which can contribute to weight gain.

It depends on the product. Some enhanced waters use non-caloric sweeteners and are calorie-free, while others are sweetened with sugar and contain calories. Always check the nutrition label to be certain.