A lighting device is provided with an illumination unit (10) including two or less LED light sources (21,22). The illumination unit (10) uses the two or less LED light sources (21,22) to emit light of a short wavelength band and light of a long wavelength band. An output varying unit (38) functions to vary an output of at least the long wavelength band light. When the output varying unit (38) receives a varying signal, the output varying unit (38) functions to decrease the output of at least the long wavelength band light.
