Benefits of Sleeping With Your Window Open (even in the winter)

Eloise (not her real name) is a 96-year-old woman who has been a patient of mine for over 15 years. She’s got some trouble with her vision, and she’s had one of her knees replaced…but besides that, she remains remarkably healthy. It’s probably no surprise to learn that she never smoked, drank very little alcohol, ate lots of vegetables, and goes for a walk every day. She credits all of those things in her health and longevity. But when I asked her what her “secret” was…her answer surprised me. She said that she ALWAYS sleeps with the window open…even in the winter here in Connecticut. “Fresh air…”  she said, “that’s my best medicine.”  

As you’ll learn in this article by my team at UpWellness…Eloise might be right.  

Enjoy, 

Dr. Josh 

Many people, especially those in European countries with mild summers, swear by keeping the window open for better night’s sleep, even in the winter. Proponents of this practice claim that soothing outdoor sounds, cool night air, and fresh oxygen all contribute to a more restful bedtime. Fortunately, there is some scientific evidence to back up this widespread belief. Read on as we delve into the top benefits of sleeping with the window open. 

Better sleep quality

One 2018 study, published in the journal Indoor Air, tracked 17 healthy individuals over 5 days; using motion sensors to monitor movement to determine restlessness throughout the night. They also measured CO2 levels and requested that participants keep a sleep diary documenting their sleep quality. Some nights, they opened the window; other nights, they kept it shut. In all cases, the nights where the window was kept open were documented as nights with more restful sleep. 

Not only is this because the outdoor air was cooler, allowing the bedroom to reach the optimal sleeping temperature (between 65-68 degrees Fahrenheit), but also because the CO2 level in the room was lower. During the study, the average CO2 level in each room was 1,150 parts per million, with the window closed and only 717 parts per million with the window open. This difference is significant enough to improve air quality and sleep efficiency by allowing better ventilation and preventing a CO2 buildup. 

Cooler temperatures

Have you ever gone to bed and cuddled up in your mountain of blankets only to wake up in the middle of the night trying to kick off as many layers as possible? Many people are unknowingly harming their sleep quality due to a hot and stuffy sleep environment. Opening up the window allows you to achieve a more restful sleep by lowering the temperature in your room. Keeping it cool means that you are more likely to cycle naturally through the three sleep stages without detrimental interruption. 

Support melatonin production

When you get adequate sleep, and you are sleeping in a room with an average temperature in the mid to high 60s, you are encouraging your body to produce more melatonin, the sleep hormone. Evidence links increased melatonin levels to brain health, cancer-fighting capabilities, and lowered diabetes, heart disease, and Alzheimer’s risk. Keeping light distraction to a minimum and stopping screen use a few hours before bed can also improve melatonin production. 

Sleeping with an open window in the winter 

People have long believed that if you sleep with your window open on a chilly winter night, you are going to catch a cold. Fortunately, this isn’t true. You catch a cold though contact with a virus, not through winter air. As long as you can stay comfortable, it is totally safe and healthy to crack your window when the temperature drops. 

Reasons to keep your window shut

You live in a polluted area

When the recycled air inside your house is fresher than the air outside, it is a good idea to keep the window shut as much as possible and use fans to keep the air moving. Invest in an air filter or purifier to help eliminate CO2 buildup and keep your indoor air clean. 

Crime is a factor

If you live on a ground floor level in a crime-ridden area, it is probably best to keep your windows tightly locked. 

It is hot and humid

Though many places experience cool, breezy summer nights, some regions remain hot and humid throughout the summer season. Sleeping in a warm room is incredibly counterproductive, so if the outdoor temperature is high, opening your windows isn’t a great idea. 

You have allergies

Unfortunately for those with seasonal allergies, the best times to sleep with your window open (spring and fall) are also prime time for that irritating sneezing and runny nose. Seasonal allergies can include sneezing, coughing, a runny or stuffy nose, and itching in the eyes, nose, mouth, and throat. Obviously, if these symptoms are worse when you’re outside, it is best to limit your exposure as much as possible.

Do you sleep with your window open? Let us know in the comments below!

-The UpWellness Team