Plain ice, which is simply frozen water, contains zero calories and therefore cannot make a person fat. Calories represent the amount of energy released when the body digests food. Since ice is pure water, it lacks the macronutrients—carbohydrates, fats, and proteins—that the body converts into energy.
The Caloric Reality of Ice
A calorie is a unit of energy. Water, in its liquid or frozen state, has no organic content that the digestive system can break down for fuel. Consuming plain ice cubes means ingesting something with zero grams of fat, carbohydrates, and protein.
The nutritional profile of water, even when frozen, is entirely devoid of the components that contribute to weight gain. This distinction is important when comparing it to other frozen treats. Flavored ice, water ice, sorbets, or popsicles, for example, often contain significant amounts of added sugars and syrups, which supply calories.
How the Body Processes Ice
The idea that eating ice could contribute to weight loss often stems from the concept of thermogenesis. Thermogenesis is the process by which the body generates heat to maintain its core temperature of approximately 98.6°F. When you consume ice or ice-cold water, your body must expend a small amount of energy, or calories, to warm the frozen mass up to body temperature.
This expenditure of energy is minimal and often described as negligible for weight management. Warming a quart of ice may burn around 140 calories, while a single glass of ice water burns only about eight calories. This is an insignificant amount compared to a person’s total daily energy expenditure. The energy used to process ice is far too small to be a meaningful weight loss strategy.
Health Concerns Related to Excessive Ice Eating
While ice consumption is not a concern for weight gain, compulsive ice eating, known as pagophagia, can signal serious underlying health issues. Pagophagia is classified as a specific form of pica, which is the craving and chewing of non-food substances. The most common and scientifically supported association for pagophagia is iron-deficiency anemia.
The craving for ice is often seen in individuals with low iron levels, and treating the iron deficiency with supplements frequently resolves the compulsion to eat ice. Some research suggests that chewing ice may temporarily increase alertness and improve cognitive processing speed in anemic individuals, potentially by triggering vascular changes that increase blood flow to the brain.
Beyond nutritional deficiencies, the physical act of chewing hard ice carries significant dental risks. Repeatedly biting down on the rigid, cold substance can lead to cracks or chips in the teeth. The habit can also gradually wear down tooth enamel, which can cause increased tooth sensitivity and make the teeth more vulnerable to decay and cavities. Existing dental work, such as fillings or crowns, may also be damaged by the pressure and temperature extremes of excessive ice chewing.