Light pollution is the artificial illumination of the sky caused by streetlights and other man-made sources. Scientists have tracked the increasing light pollution with data from NASA photos compiled in the New World Atlas. Several decades ago, one could go out and see the Milky Way and countless stars in Davis County. With light pollution burgeoning and light readings along the Wasatch Front at midnight rivaling large cities along the coasts, some residents would be lucky to see the Big Dipper. According to researchers at James Madison University, exposure to light during sleeping hours can disrupt natural sleep/wake cycles and reduce production of melatonin – the sleep hormone. In fact, light pollution has been linked to heart disease and cancer, as well as other health challenges like sleep disorders, obesity, anxiety, depression, and diabetes.

Many people enjoy the artificial light available all night. Barbara Bryner of Bountiful feels the light deters burglars and gives her enough light to move around carefully through the house at night without turning on any lights. 

Her neighbor, Carol Kerr, however, feels too much light keeps her from sleeping well and may contribute to her heart racing at night. “That could be why my heart is going wacky,” said Kerr. “Turn off the light!”  

Some research out of JMU does show that exposure to even dim light during sleep can raise heart rate and blood pressure. Kerr lived in Alaska for many years and is familiar with the difficulty associated with having light all night long and its obvious effect on sleep quality. 

Bryant Dresher, who lives in a very bright area of Bountiful, thinks reducing the light pollution may help their daughter improve her sleep. “Your body is naturally going to produce the melatonin when it gets darker,” said Dresher. “If it doesn’t get darker then it doesn’t naturally turn that on.” 

High levels of melatonin have been shown to stop the growth of cancerous cells. In a several studies out of the University of Haifa in Israel on Light At Night (LAN), a neighborhood where you could read a book at midnight because of the high light pollution, showed marked increases in both the occurrence of breast cancer in women and prostate cancer in men. Additionally, Dark Sky advocates of a healthful dark night noting that those who fall asleep in front of a screen emitting blue light are more likely to be obese and to continue to gain weight. Closely related, exposure to light during sleeping hours can increase insulin resistance and the development of diabetes. Light pollution also affects wildlife. Mating and foraging practices can be influenced and stress in various animal populations has been documented.

It is not necessary to stumble around in the dark, Dark Sky notes, if light is needed at night, warmer tones with an amber look are better than the bright blue light. Light that faces downward has a much lower impact on LAN than lights that emit light sideways, or even worse, upward.

Christmas lights have morphed into permanent security lights on many new homes with a barrage of a color and light show year round. In 2008, National Geographic wrote an article on “Our Vanishing Night,” which included a two-page photo of the Bountiful Temple bathed in an aurora of light. 

The upside of light pollution is that it can be easily and completely stopped simply by turning off the lights. Security lights can be motion-activated. Amber lights can replace the sleep depriving blues. Shading windows can be helpful, but be mindful that part of the healthy sleep/wake cycle is exposure to sunlight in the morning. Light needs to be balanced with darkness. Every day needs a night. λ