System, comprising - a holder for fastening a luminous body to a ceiling element or to a wall element, comprising a substantially cylindrical base body which extends along a longitudinal axis from a base body start to a base body end and has an outer lateral surface, wherein an element for adjustable fixing in the direction of the longitudinal axis is arranged on the outer lateral surface, in particular an external thread, wherein at least one filler element is arranged in the region of the base body end, which filler element projects from the base body in a first direction, wherein the first direction has at least one directional component, which directional component lies in a normal plane disposed perpendicularly to the longitudinal axis, wherein the holder further comprises at least one plate element, wherein the plate element has a, preferably cylindrical, opening, in which opening the base body is held by means of the element for adjustable fixing in the direction of the longitudinal axis, in particular by means of the external thread by a screw connection, and - at least one luminous body, wherein the luminous body can be arranged in an interior of the base body in a detachable manner, in particular in a detachable manner without tools, characterized in that the holder comprises at least one cooling element and at least one connection board for an electrical connection of the luminous body, wherein the cooling element is connected to the base body in the region of the base body start, and wherein the cooling element has a larger diameter perpendicular to the longitudinal axis than the opening, and in that the at least one luminous body comprises a circuit board, in particular a circuit board having at least one light-emitting diode, which circuit board can be placed in a corresponding recess of the connection board and can be contacted with the cooling element. - a holder for fastening a luminous body to a ceiling element or to a wall element, comprising a substantially cylindrical base body which extends along a longitudinal axis from a base body start to a base body end and has an outer lateral surface, wherein an element for adjustable fixing in the direction of the longitudinal axis is arranged on the outer lateral surface, in particular an external thread, wherein at least one filler element is arranged in the region of the base body end, which filler element projects from the base body in a first direction, wherein the first direction has at least one directional component, which directional component lies in a normal plane disposed perpendicularly to the longitudinal axis, wherein the holder further comprises at least one plate element, wherein the plate element has a, preferably cylindrical, opening, in which opening the base body is held by means of the element for adjustable fixing in the direction of the longitudinal axis, in particular by means of the external thread by a screw connection, and - at least one luminous body, wherein the luminous body can be arranged in an interior of the base body in a detachable manner, in particular in a detachable manner without tools, the holder comprises at least one cooling element and at least one connection board for an electrical connection of the luminous body, wherein the cooling element is connected to the base body in the region of the base body start, and wherein the cooling element has a larger diameter perpendicular to the longitudinal axis than the opening, and in that the at least one luminous body comprises a circuit board, in particular a circuit board having at least one light-emitting diode, which circuit board can be placed in a corresponding recess of the connection board and can be contacted with the cooling element.