Why You Should Turn the Thermostat Down Before Going to Bed
Energy Star, a federal program, recently made waves when it suggested 82 degrees as the ideal temperature for sleep to help consumers save money on their energy bills. Many people on social media were outraged—and for good reason. Temperatures above 75 degrees (and below 54 degrees) are known to interfere with sleep, says Terry Cralle, RN, certified clinical sleep educator and Saatva sleep consult.
"The suggested bedroom temperature for optimal sleep is between 60 and 67 degrees Fahrenheit," says Cralle.
That said, what's comfortable for one person might not be comfortable for another. How many times have you turned the thermostat up a couple of ticks only to have your partner follow right behind you and turn it down?
Here, learn all about how temperature impacts your sleep, the health benefits that come from sleeping in a cooler bedroom, and what you can do to ensure you're comfortable while you snooze, no matter the temperature.
How room temperature affects your body temperature
“When you sleep, your body's internal temperature drops to its lowest level," Cralle says. A person's body temperature varies throughout the day, she explains, rising about one to two degrees from early morning until late afternoon and hitting its lowest point several hours before waking up in the morning.
As your energy goes down in the evening and you become drowsy, your body's temperature goes down along with it. “In preparation for sleep, blood vessels dilate, which causes a decrease in core body temperature," says Cralle. This drop, in turn, initiates sleepiness.
So what does room temperature have to do with this? During sleep, your brain takes a break from regulating your body temperature—which means that a room that's too cold or too hot could disrupt your sleep and potentially cause you to wake up in the middle of the night.
The health benefits of sleeping in a cool room
As you already know, sleep impacts your general health in a variety of ways—and sleeping in a cooler bedroom, in particular, has some serious advantages.
For starters, it can help ease insomnia. Cralle points out that some studies have shown that certain forms of insomnia are associated with an improper regulation of body temperature. As noted in a study from the University of South Australia, insomniacs have a warmer core body temperature immediately before initiating sleep. Since a warm core temperature signals wakefulness and alertness, the body gets a bit confused.
“According to the research, our brains love a cool sleeping temperature," Cralle says, citing a study from the American Academy of Sleep Medicine, which shares that wearing a cooling cap to bed can help insomniacs sleep.
Ideal sleep temperature can also improve metabolic health (i.e. your cholesterol, blood pressure, and blood sugar). According to Cralle, “a colder body temperature boosts production of brown fat, which is a type of fat that burns calories instead of storing them," a fact that was confirmed by a 2014 study from the American Diabetes Association.
“When study subjects slept in a cooler environment, they gained metabolic advantages," explains Cralle. "The researchers stated that these advantages could reduce their risk of diabetes as well as other metabolic problems. The study subjects also burned a few more calories throughout the day when they slept in a cooler environment."
Sleeping in a cooler bedroom can also help improve your sleep if you have night sweats. Night sweats are a common occurrence for people going through menopause, but they can also happen to those with other hormonal imbalances, such as serotonin imbalances, and those who take medications that regulate hormone levels.
Other common causes of night sweats include hyperhidrosis (a condition in which the body sweats excessively without clear cause), anxiety, and low blood sugar (usually in people who take medications to lower blood sugar, like diabetics).
Finally, body temperature does more than keep you sleeping comfortably—it serves a key role in regulating circadian rhythm, the body's internal "clock" that helps determine sleep and wake cycles.
Best mattress to help achieve ideal sleeping temperature
Ambient temperature in the room isn't the only thing that affects how warm or cool you'll sleep. “When it comes to a comfortable sleeping temperature, consider your mattress and your bedding," she says. “The materials of your sheets, of your pajamas, as well as the materials in your mattress can affect your sleeping temperature, which in turn, affects your sleep." Fabrics like organic cotton are breathable and will help you sleep cool.