Since there even exists led ear plugs that modify your function so much it can be measured i guess also ambient light can have effect. If you see a difference when the eyes are closed (red light penetrates eyelids at very low power) it changes your chemistry.Is the light beneficial while sleeping at all? If theres no benefit to it I wont. Im just sure I remember reading something from peat saying sleeping jn darkness can be stressful
While any kind of normal light greatly prevents me from falling asleep, red light actually encourages a meditative state and it helps falling asleep.