Blue Light and Sleep: What's the Connection? ~ JPEEI CLINIC
September 15, 2021 Sleep No comments
Poor sleep is linked to heart disease, type 2 diabetes, depression, and obesity.
The use of artificial lighting and electronics at night may contribute to sleep problems. These devices emit light of a blue wavelength, which may trick your brain into thinking it’s daytime (5Trusted Source).
Many studies suggest that blue light in the evening disrupts your brain’s natural sleep-wake cycles, which are crucial for optimal health (6, 7Trusted Source).
Most importantly, it determines when your body is primed for being awake or asleep (9Trusted Source).
Keep in mind that sunlight and white light contain a mixture of various wavelengths, each of which has a significant amount of blue light (10Trusted Source).
Getting blue light, especially from the sun, in the daytime helps you stay alert while improving performance and mood (11Trusted Source).
Blue light therapy devices may help treat depression, and blue light bulbs have been shown to reduce fatigue and improve the mood, performance, and sleep of office workers (12Trusted Source, 13Trusted Source, 14Trusted Source).
Blue light, whether from the sun or a laptop, is very effective at inhibiting melatonin production — thus reducing both the quantity and quality of your sleep (15Trusted Source, 16Trusted Source).
Studies link melatonin suppression in the evening to various health problems, including metabolic syndrome, obesity, cancer, and depression (17Trusted Source, 18Trusted Source, 19Trusted Source, 20Trusted Source).
Studies show that when people use blue-light-blocking glasses, even in a lit room or while using an electronic device, they produce just as much melatonin as if it were dark (21Trusted Source, 22Trusted Source).
In one 2-week study, 20 individuals used either blue-light-blocking glasses or glasses that didn’t block blue light for 3 hours before bedtime. The former group experienced major improvements in both sleep quality and mood (24Trusted Source).
These glasses have also been found to greatly improve sleep in shift workers when worn before bedtime (25Trusted Source).
What’s more, in a study in older adults with cataracts, blue-light-blocking lenses improved sleep and significantly reduced daytime dysfunction (26Trusted Source).
That said, not all studies support the use of blue-light-blocking lenses or glasses. One analysis of several studies concluded that there’s a lack of high quality evidence supporting their use (27Trusted Source).