Leaving a small light on while you sleep or keeping your curtains open to allow some light into your bedroom: many people don’t sleep completely in the dark. But did you know that this is actually not good for your health at all?
From research by the Northwestern University Feinberg School of Medicine in Chicago, exposure to light while sleeping poses many health risks.
Before the study, participants were monitored for seven days. Just under half of the participants slept in a pitch dark room. The others slept with some light in the room. And guess what? Sleeping with lights on increased the chance of developing high blood pressure by 74 percent. And even more intense: the chance of developing obesity increased by 82 percent and the risk of diabetes even by one hundred percent!
Participants were also tested whether sleeping with light increases the risk of hypercholesterolemia, but the researchers saw no difference.
Health risks also in young people
You might think that the danger of light while sleeping only lurks for the elderly, but nothing could be further from the truth. Exposure to dim light overnight can also increase heart rate and blood glucose in young and healthy people.
What makes sleeping with the light on so harmful?
Your brain uses the presence of light as a kind of clock. Light indicates when to be awake and when it is time to go to sleep. Exposure to light activates the sympathetic nervous system and causes your heart rate to increase. Actually, your body is getting the signal that it is time to get active for the day.
At night the parasympathetic nervous system starts working. This ensures that your body can relax and recover. It lowers your heart rate and maintains a healthy metabolism. In addition, your brain produces the sleep hormone melatonin, which signals your body when it is time to go to sleep. Exposure to light suppresses the production of melatonin, which disrupts the healthy and natural sleep pattern.
What can you do against the light?
Often there is not much you can do about light entering your bedroom. For example, by a street lamp in front of your window. But there are some things you can do to mitigate the risks.
First of all, you can of course opt for a few good blackout curtains that block out the light from outside. It is also important to switch off devices that produce light, such as a television or smartphone, before and during sleep. Is it still light in your room? Then purchase a sleep mask that covers your eyes. You can also choose to purchase a night light with a motion sensor. It only turns on when you get out of bed.
Bron: Real Simple, Women’s Health
Foto: Getty Images
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