There are many factors that can affect the quantity and quality of sleep you get each night. From having too much to eat and drink close to bedtime to sleeping next to someone who snores, you run the risk of waking up feeling like you never went to sleep. One factor that you may unknowingly be exposed to every night that is impacting your sleep is light pollution.
Light pollution refers to any artificial indoor or outdoor light. This can include street lamps, patio or backyard lighting, nightlights, car headlights, storefront signs, televisions, smartphones, computer monitors and any other non-natural light at night. Outdoor light pollution is typically associated with urban areas, but can occur anywhere light is used in an area that would otherwise be dark.
Light Pollution and Sleep
Your body’s ability to determine when you are awake and alert or when you are sleepy and less energetic is controlled by your circadian rhythm. A 24-hour clock that also controls when you feel hungry, your circadian cycle works best when you go to bed and wake around the same time every day. However, many environmental influences like light pollution can disrupt that cycle and result in poor quality sleep or no sleep at all.
Besides feeling tired and grumpy, there are other consequences associated with a disruption in your circadian rhythm from light pollution. Your internal body clock may tell you to fall asleep and wake earlier than you want. You may have trouble staying asleep or you may wake in the middle of the night and be unable to return to sleep.
How Light Disrupts Your Sleep
If your sleep patterns remain disrupted for a long period, you become chronically sleep-deprived and may even be diagnosed with insomnia. Some people who suffer from insomnia may turn to sleeping pills for relief, but long-term use of such drugs may become habit-forming or addictive.
A disruption in your circadian cycle is associated with several disorders and diseases. When you miss out on restful sleep, you are at an increased risk of developing early-onset diabetes, depression, heart disease, prostate cancer, and breast cancer.
Impact of Artificial Light
Artificial night light may also affect your body’s ability to produce melatonin. Melatonin is a hormone that your body naturally secretes at night to help regulate your internal clock. When the sun sets, melatonin levels begin to rise and will remain elevated until it starts to get light. The artificial night light coming from a window or television interferes with this process by suppressing melatonin production, delaying feelings of drowsiness, and making it much more difficult to get a full night’s sleep.
You don’t just have to be concerned with the amount of artificial night light you are being exposed to. The type of light is important as well. Studies show that the blue light emitted from LED light bulbs and your electronics can suppress your melatonin levels and interfere with your circadian rhythm much more than other types of lights. This means your late-night movie watching habit can make you more susceptible to sleep problems than that pesky street light.