The invention relates to a method for operating an internal combustion engine, in particular a diesel engine. An external exhaust gas recirculation device is provided, exhaust gas emitted by an internal combustion engine is supplied to the internal combustion engine again by virtue of the external exhaust gas recirculation device, the exhaust gas recirculation device has a recirculation setting device by virtue of which the flow of recirculated exhaust gas can be set, a closing time setting device is provided by virtue of which the closing time of at least one inlet valve of the internal combustion engine can be adjusted, by virtue of the closing time setting device, the basic cycle of the internal combustion engine can be set, and at least one inlet valve of the internal combustion engine is closed in a crank angle range of 1 degree to 40 degrees, particularly from 10 degrees to 40 degrees after DBC. For reduction of nitrogen oxides emitted by the internal combustion engine, a nitrogen oxide reduction cycle can be set by virtue of the closing time setting device, and a control unit is provided which performs regulation and/or control using the closing time setting device and the recirculation setting device as a function of torque of the internal combustion engine.