Red LEDs create light through semiconductors and electronics, not heat. Instead of emitting all colors of light and filtering them naturally, LEDs produce a single, narrow spike at one specific wavelength, which is then driven electronically to appear red.
Because this light is generated by electronic circuits, it is tied to AC power and rapid on-off switching. There is no infrared output, no gradual falloff, and none of the depth found in heat-based light. Human biology did not evolve under this type of electronically generated spectrum.
While red LEDs may look similar at a glance, their narrow, artificial output interacts differently with the eyes and nervous system, lacking the qualities present in real, heat-based light from ancestral environments.