Many parts of the world are experiencing extreme heat waves right now, and some people are having trouble sleeping as a result.
In fact, researchers have shown that the temperature of your surroundings is one of the most important factors in getting a good night’s sleep. Scientists are especially interested in understanding the effects of high temperatures on the quantity and quality of sleep. So far, they’ve found that there’s a strong link between unbearable heat and insufficient sleep. High nighttime temperatures have been found to be directly correlated to self-reported nights of poor sleep.
According to the National Sleep Foundation, when temperatures are very high, it takes longer to fall asleep and stay asleep. You sleep better when your body is in a cool environment, which averages from about 65 and 72 degrees Fahrenheit for most people. Any higher, the body struggles to regulate itself in the extreme conditions.
We know that sleep is an important factor in just about everything we do. That means that creating a comfortable sleep environment is vital not only for quality shuteye but also for productive daytime activities and good health. The following are the consequences that extreme heat can have on your sleep.
Heat affects your circadian rhythms
The body’s natural process of thermoregulation—the maintenance and adjustment of its core temperature—operates on a 24-hour circadian cycle. Dropping and rising body temperatures play a major role in the body’s sleep-wake cycle: decreasing body temperature helps you fall asleep and stay asleep at night, and increasing temperature wakes you up in the morning. But when the body’s circadian thermoregulation is thrown out of whack by temperatures that are just too high, normal sleep processes are badly disrupted.
High temperatures increase wakefulness
As stated above, an increase in core body temperature stimulates alertness in the morning. So if you’re too hot in the middle of the night, you might struggle to fall asleep in the first place, or wake up more often than you’d like.
Severe warm weather decreases slow wave sleep (SWS)
Slow-wave sleep (SWS), often referred to as deep sleep, consists of stage three (combined stages three and four) of non-rapid eye movement sleep. Slow-wave sleep is important for memory consolidation, making it crucial that your body doesn’t lose this quality rest to the unformidable heat.
Hot spells decrease rapid eye movement (REM) sleep
Your bedroom temperature can especially take a toll on the quality of your REM (rapid eye movement) sleep, the time of night in which dreaming occurs. During REM sleep, the brain is very active, and yet, with the exception of the heart and lungs, the muscles of the body are still. According to the National Sleep Foundation, REM sleep is believed to benefit learning, memory, and mood. If high heat is costing you essential REM sleep, you’re at a greater risk of reduced coping skills, poor cognitive function, migraines and being overweight.
Sources:
https://sleepfoundation.org/sleep-news/sleeping-when-it-blistering-hot
https://jphysiolanthropol.biomedcentral.com/articles/10.1186/1880-6805-31-14
http://advances.sciencemag.org/content/3/5/e1601555.full
https://www.ncbi.nlm.nih.gov/pubmed/15173935
http://www.centerforsoundsleep.com/sleep-disorders/stages-of-sleep/
https://sleepfoundation.org/sleep-news/rem-sleep-deprivation-and-migraines
https://www.medicalnewstoday.com/articles/247927.php
