A study by a team of Swiss, Japanese and Georgian researchers has shown that LED lighting with high melanopic efficiency and a spectral profile mimicking that of the sun improves visual comfort, mood, alertness and sleep compared to conventional LED lighting.

Lighting with procognitive LEDs had a positive effect on mood, improving participants’ alertness and happiness compared to conventional LEDs.

Participants in the study overwhelmingly reported that they ‘felt happier, more alert and more satisfied in the morning and evening with full-spectrum LED lighting than with standard LED lighting‘. DayLED lighting, which better mimics the natural light patterns of the sun, helps to regulate mood more effectively in line with the body’s circadian rhythms. In contrast, conventional LED lighting does not secure this effect.

Exposure to standard LED lighting resulted in a delayed onset of melatonin production, whereas full-spectrum LED lighting did not show these effects.

Nocturnal melatonin levels, measured from the saliva of research participants, remained the same after exposure to full-spectrum LEDs during the day. In contrast, conventional LED daylighting slowed the production of nocturnal melatonin.

LED lighting with a spectral composition modelled after the sun improved sleep quality compared to standard LED.

After exposure to full-spectrum LED lighting during the day (dayLED), higher delta EEG activity (0.75-4.5 Hz) was recorded at night, which is associated with a deep phase of non-REM sleep. This suggests that procognitive LED lighting improves the depth and quality of sleep compared to conventional LED lighting. Other studies conducted under controlled conditions also confirm the positive effects of LED daylight on sleep in healthy subjects.