Blue Light Has Beneficial Effect on Mood
“Blue light has been found to be particularly beneficial for boosting your mood — more so than red or green light. While the light used in the featured study included wavelengths between approximately 440 nm and 710 nm (violet, blue, green, yellow, and red light), the impact of blue light on mood could potentially account for some of the benefits seen in this study.
For reference, UVB and UVA, the former of which boosts vitamin D, and the latter of which is associated with skin damage, have wavelengths between 290 and 400 nm. Blue light has a wavelength of about 500 nm, followed by green, and yellow in the 600 nm range.
According to one 2010 study,10 blue light appears to play a key role in your brain’s ability to process emotions, and its results suggest that spending more time in blue-enriched light could help prevent and/or treat SAD and depression. Blue light is prevalent in outdoor light, so your body absorbs the most during the summer and much less in the winter.
Because of this, researchers have suggested that adding blue light to indoor lighting, as opposed to the standard yellow lights typically used, may help boost mood and productivity year-round, and especially during the winter.
Keep in mind however that blue light at night should be avoided, as it can impair your sleep. One of the reasons for insomnia and poor sleep is due to excessive exposure to blue light-emitting technologies such as TV and computer screens. The blue light depresses melatonin production, thereby preventing you from feeling sleepy.”