Observing Jews generally cannot eat at standard mainstream McDonald's restaurants because the vast majority of their menu items fail to meet kosher dietary requirements, as they serve non-kosher meats, combine cheeseburgers containing both dairy and meat, and do not operate under rabbinical supervision. However, McDonald's does operate fully certified kosher locations in specific regions, most notably in parts of Israel, where the ingredients, food preparation processes, and operational schedules comply completely with Jewish dietary laws, including closing entirely during the Sabbath and major religious holidays.