Mouthwash is commonly used to enhance dental hygiene, freshen breath, and deliver therapeutic agents like fluoride. Rinsing with this liquid often raises questions about its nutritional content, particularly its caloric value. Some mouthwashes do contain trace calories, but the amount is generally considered negligible for most users. This minimal caloric content is tied to specific ingredients used in the formulation.
Where Do Trace Calories Come From?
The minor caloric content in mouthwash originates from ingredients used as solvents, humectants, and flavor enhancers. Alcohol, typically ethanol, is a frequent component in many traditional formulas, often ranging from 5% to 27% by volume. Ethanol serves as a solvent and preservative, contributing approximately seven calories per gram.
Calories also come from humectants and sweeteners added to improve texture and taste. Glycerin (glycerol) is a common humectant that provides a smooth feel and sweetness. Glycerin is classified as a sugar alcohol and contains about 4.32 calories per gram. Other nutritive sweeteners, like sorbitol, may also be included for palatability, contributing a small number of calories.
The Importance of Rinsing and Absorption
Concerns about mouthwash calories stem from the difference between ingestion and rinsing. The product is designed to be swished and then spat out, meaning the caloric components are not intended to be swallowed or digested. When used as directed, the amount accidentally swallowed is minimal, often just residual drops.
A standard rinse uses a small volume, typically 10 to 20 milliliters, and the vast majority is expelled. Metabolic processes required to extract energy from ingredients like alcohol or glycerin happen in the stomach and intestines after ingestion. While some alcohol can be absorbed sublingually through the mouth tissues, the amount from a typical rinse is so small that the caloric impact is practically zero. Therefore, for individuals tracking macronutrients or fasting, the trace calories from a proper mouthwash rinse are not a factor.
Calorie Differences in Mouthwash Types
The specific formulation dictates the caloric difference between various mouthwash products. Alcohol-based formulas contain a higher potential for trace calories due to the energy content of ethanol. If intentionally swallowed, these traditional rinses could contain 5 to 10 calories per capful, mostly from the alcohol.
In contrast, alcohol-free mouthwashes contain significantly fewer calories. These formulas replace ethanol with non-caloric solvents and rely on non-nutritive sweeteners, such as sucralose or sodium saccharin, to enhance flavor. Therapeutic or prescription-strength rinses may also contain different caloric buffers. However, since all mouthwashes are intended for rinsing and not ingestion, their caloric contribution remains insignificant. Intentional consumption is strongly discouraged due to the potential toxicity of active ingredients like fluoride.