Collections > UNC Chapel Hill Undergraduate Honors Theses Collection > A Randomized Trial of the Impact of Amber Versus Blue Glasses on Sleep Quality, Energy and Mood

The connections between sleep and mood disorders have prompted speculation in the field of psychology for some time. The human circadian rhythm, the biological mechanism which has a significant impact on the diurnal highs and lows of both wakefulness and mood, is impacted by a variety of endogenous and exogenous factors. One of the most potent of these factors is light, but it has recently been proven that the absence or presence of blue wavelength light (446-477 nm) has a particularly strong effect. With the use of blue light blocking amber lenses, one may be able to influence and regulate sleep, mood and potentially mental health for the better, especially in individuals for whom these cycles are disrupted. In a randomized trial, 27 students at the University of North Carolina at Chapel Hill, aged 18-26, wore either control blue or experimental amber lenses for three hours prior to their own calculated average bedtime for 12 days of an 18 day protocol. Participants completed self-report measures of sleep quality, mood, and somatic complaints on a daily basis, and more precise measures of sleep quality every 6 days. The first 6 days when they did not wear glasses were compared to the later 12 days during which they did wear the blue or amber glasses. There was a significant improvement in sleep, energy, and mood when participants wore the amber and blue glasses (p < .005), but there was no difference between the two conditions. Future directions could include the use of more objective sleep measures and testing glasses of different colors.