The invention relates to an internal combustion engine (1) with a crankcase (3) and a cylinder head (4) having exhaust ports (9) feeding into an exhaust manifold (10) for exhaust gas from the combustion chambers (5) of the internal combustion engine (1). Provision is hereby made for the cylinder head (4) to include at least one region of a heating channel (12) which is different from the exhaust ports (9) and the exhaust manifold (10) and has an inlet side (14) branching from one of the exhaust ports (9) or the exhaust manifold (10), and which is flowed through by an exhaust mass flow that is adjustable by an actuator (13). The invention further relates to a method for operating an internal combustion engine (1).