Nighttime Light May Be Hurting Your Sleep—And Your Health
Exploring a new study and what you can do to combat light leak sleep problems
Many people know how difficult it can be to fall asleep in a brightly lit room, but did you know that even a little bit of light could be messing with your shut-eye? According to a new study, not only can a moderate amount of light disrupt your sleep—it can also lead to poor sleep quality, weight gain and in some cases, eye strain. From sleeping with a night light, living in a bustling city where the lights outside your window never completely go out. to sleeping with the TV on, it can be hard to prevent light from seeping into the bedroom during our sleeping hours. Some of the habits people might think help them sleep better, may not. We’ve dug into the studies and also thought through products and habits that could help combat this issue.
Why and how does light leak negatively impact sleep and metabolic health?
The researchers conducting this latest study focused on two groups of sleepers. During the first night of the study, both groups slept in fully dark rooms while researchers gathered base-line data. The second night, the researchers kept one group in the dark—sleeping room, that is—while the other group slept in a room that was lightly lit with 100 lux of artificial light—just enough light to see, but not enough to comfortably read. By measuring physiological responses like heart rate and blood sugar, the researchers were able to see a key division between the two groups. The sleepers in the room with even that little bit of light exhibited increased heart rates throughout the night and insulin resistance in the morning, meaning they struggled to get their blood sugar to a normal range.
Some other interesting highlights include:
- Sleepers in the lit rooms felt like they slept fine. They could not tell their sleep had been disrupted.
- Artificial light at night can suppress melatonin levels which is part of why it contributes to a disrupted sleep/wake cycle.
- Melatonin disruption is also linked with a higher likelihood of cancer or diabetes.
- Elevated heart rates in sleepers who were exposed to light indicate that even a little bit of light can keep the nervous system activated and alert, causing the sleeper to get less deep sleep and possibly less recovery since their nervous system is not at rest.
- Disrupting circadian rhythms can make it harder for the body to regulate blood-glucose levels which can lead to weight gain, diabetes and other cardiometabolic issues.
This data may seem a little overwhelming in some ways – it can be both surprising and challenging that something as seemingly innocuous as a night light could have possibly debilitating long-term health effects. But there are preventative actions one can take to help! The study also speaks to how necessary it is to get your sleep environment just right.
How to help curb light leaking habits and conditions?
Light Leak Problem: I can’t sleep without a TV on
Possible Solution: Try opting for a radio, music or some other ambient noise. It seems unlikely that it’s the flickering light of the TV that helps you sleep, but often the sound. If you live in a multi-unit building, you might use ambient noise to dampen sound from other units or outside the window—the same goes for if you live in a too-quiet house and are looking to mask any slight noises. Of course, sometimes we all accidentally fall asleep watching TV— but as long as it doesn’t become an every night thing, you should be ok.
Light Leak Problem: My apartment or home faces a well-lit or busy street
Possible Solution: Bring on the black-out curtains, baby! Light blocking curtains or thick shades can help deliver privacy, keep light out, keep heat or cold in and even muffle sound. They are a city-dweller’s best friend.
Light Leak Problem: I am afraid of the dark and need a night-light
Possible Solution: If you must use a night light, opt for a red bulb. While further research might need to be done (many of the studies on the topic are from 2012-2015), red light does not appear to have the same negative effect on sleep as other types of artificial light. More on that here and here.
Light Leak Problem: I struggle to wind down in the evening (hence the TV, light at night for reading, etc.)
Possible Solution: There are even more holistic approaches to addressing both the light leak issue along with larger sleep issues as well. Light leak also includes phones and technology that could turn on in the night. By developing a regimented wind-down practice, you can both cue your brain that it’s time for sleep and also prevent any unwanted disruptions throughout the night. Try incorporating accessories like an eye mask, light blocking window coverings, and taking steps like turning off or putting technology on do-not disturb and night-modes.
Light Leak Problem: I have trouble shutting down technology at night—some of my devices are even meant to help with sleep
Possible Solutions: Make a concerted effort to either turn your phone off at night, put it away from your bed or put it on a do not disturb setting. Consider using sleep technology that offers voice control so you do not need to use a light-up remote. Use an old-fashioned alarm so you don’t have to rely so heavily on your phone or other light-up technologies.
