The link between good health and quality of sleep has been known for decades. A recent study into the light levels during sleep and human health have highlighted the need for darkness. The study results found that light pollution during sleeping hours may be linked to obesity in women and an increase in diabetes risks.
A team of researchers at Northwestern University enlisted the help of twenty people to monitor their sleep patterns over several nights. Phyllis Zee and her team observed test subjects during their sleep, drawing blood and tracking their sleep patterns every four hours. Researchers looked into the reaction of test subjects to light during their sleeping hours while providing large doses of sugar each morning.
On the first night, twenty individuals slept in a darkened room. However, on the second night, the light levels were risen for some subjects to monitor the difference in reaction.
The researchers used standard sleeping practices with a nightlight or muted TV on some test subjects. With those subjects, they observed increased heart rates during sleep.
Phyllis Zee’s team focused their study on exploring how the processing of sugar and insulin resistance are affected by sleep patterns. The Northwestern University team discovered that sleeping in a well-lit room made it more difficult to process sugar. This link between light and insulin resistance could have significant impacts on obesity, and the populations’ ability to process sugar.
The study also demonstrated data linking light exposure and restlessness. A small amount of light supplied enough arousal to disturb the sleep of the test subjects. However, a proposed link between low melatonin production and light levels is not proven.
Phyllis Zee acknowledged the study’s limitations, which monitored a small number of subjects for very few nights. In the future, Zee would like to lead a more extensive study to explore the long-term effects of light on sleep-wake patterns.
The use of smartphones and tablets in the bedroom has increased dramatically. The team at Northwestern University explained they would also like to focus on the impact of technology in the bedroom by exploring the effect of blue light on sleep-wake patterns.