Black coffee, defined as plain brewed coffee without any additives, contains only trace amounts of carbohydrates. From a nutritional standpoint, this beverage is nearly free of all macronutrients, making it an extremely low-calorie and low-carb option. The brewing process extracts compounds from the roasted bean using hot water, but the resulting liquid is predominantly water. The minimal carbohydrate content is too small to register a meaningful impact on daily intake.
The Definitive Carb Count of Black Coffee
A standard eight-ounce cup of black coffee typically contains less than one gram of total carbohydrates. Nutritional labels often round this figure down, stating the carbohydrate content as zero grams per serving. This near-zero count makes black coffee a favorable choice for individuals monitoring their macronutrient intake closely.
For those following strict dietary patterns, such as ketogenic diets, black coffee is considered a “zero-carb” beverage that does not interfere with ketosis. The caloric contribution is also minimal, usually only two to five calories per cup, coming from trace amounts of protein and lipids.
Understanding Trace Carbohydrate Sources
The minimal carbohydrates found in the final cup originate from the complex composition of the roasted coffee bean itself. Carbohydrates constitute about half of the dry weight of a green coffee bean, primarily as large, insoluble polysaccharides. During roasting, some of these large molecules degrade into smaller, water-soluble compounds, including minor sugars.
When coffee is brewed, only a small fraction of the bean’s components are extracted into the water. These trace carbohydrates are the water-soluble compounds that dissolve during brewing. The majority of the complex, fibrous carbohydrates remain trapped within the spent coffee grounds, explaining why the resulting liquid is low in carbohydrates compared to the raw bean.
How Additions Change the Macronutrient Profile
The carbohydrate profile of a coffee beverage changes drastically the moment any ingredient other than water is introduced. The majority of carbohydrates consumed in coffee come from milk, sugar, and flavorings. For example, adding just two tablespoons of whole dairy milk contributes approximately one to two grams of carbohydrates, primarily from the naturally occurring milk sugar, lactose.
The use of flavored syrups, a common coffee shop addition, can quickly turn a low-carb drink into a high-sugar dessert. A single pump of a standard flavored syrup can contain five grams of carbohydrates, almost all of which are added sugars. Even non-dairy alternatives, such as oat milk or sweetened almond milk, can add significant carbohydrates, as they often contain starches, stabilizers, or added sugars to improve taste and texture. A single 16-ounce latte made with dairy milk and flavored syrup can easily contain 20 to 40 grams of carbohydrates, proving that the additions, not the coffee base, are the primary source of carbs.