High-fat diets produce insulin resistance, but it is not known how quickly changes become evident or whether different types of fat produce different responses. The aim of this study was to determine whether a high-fat evening meal affected glucose response to a standard breakfast 12 h later. On six occasions eight weight-stable subjects consumed a standard evening meal (109 g carbohydrate, 27 g protein, 6 g fat, and 10.6 g fiber) that was either unsupplemented or supplemented with 41 g fat (safflower oil, olive oil, butter, or medium-chain triglyceride) or 75 g carbohydrate followed by a standard breakfast. Glucose, insulin, and free fatty acid responses were measured over 3 h. There were no differences in metabolic responses to the standard breakfast after the different evening meals, indicating that a single high-fat meal has no deleterious effects on carbohydrate metabolism 12 h later, regardless of the type of fat ingested.