Sure, those Christmas socks aren’t the most stylish, but keeping your feet warm at night has been proven to actually makes a difference in your sleeping patterns. According to sleep.org, “Heating cold feet causes vasodilation—dilation of the blood vessels—which may tell the brain that it is bedtime. After the blood vessels open in the hands and feet, heat is redistributed throughout the body to prepare for sleep.”
In other words, keeping your feet warm in bed helps you have less restless nights. It also results in falling asleep at a quicker rate. In case you’re not convinced, here’s a study that was published in the International Weekly Journal of Science that says hitting the hay with socks on actually helps you fall asleep fifteen minutes sooner than usual. Wearing socks to bed is also useful in aiding hot flashes, improving dry feet, and increasing orgasms.
Traditional Chinese medicine also backs up this wear-socks-to-bed concept, specifically focusing on its ability to enhance circulation. “Cold feet can drain the energy of the body and can obstruct the flow of vital qi (energy) and blood (nutrition) in the body. For that reason we want to circulate the ‘qi and blood.’
By doing so we keep painful obstruction away from the body and keep the energy flowing smoothly,” Dr. Elizabeth Trattner A.P. DOM, Doctor of Chinese and Integrative Medicine, told Reader’s Digest. “Cold impedes the flow of energy and heat or warmth encourages it. If you think about a warm bath you relax, and in cold water you tense up. Cold creates stagnation which can also lead to pain (think Reynaud’s Syndrome).”
Essentially it’s all about core body temperature. If you get too hot at night, your sleep will be disturbed
The sleep/socks question has at least four aspects:
- hygiene (sweaty feet….hmmmm)
- aesthetics (not exactly a fashion statement)
- procreation (neither are they an aphrodisiac)
- sleep science (the right heat = happy feet = happy sleep)
Here’s the science bit
Humans are endotherms. Unlike lizards, who need to bask in the sun to start their day, we are able to the moregulate ie we can maintain our own body temperature.
Thermoregulation is clever stuff (here’s an explainer) Essentially it ensures our vital organs are always operating at the optimal temperature. Anywhere outside the range 92.3 -104.9 F and you’ll be in serious trouble.. or dead.
Typical body temperature throughout the day
In normal sleepers body temperature is lower at night than it is during the day. This temperature drop starts at the onset of tiredness and continues to around 4am in the morning. Research has shown that a cool room is optimal for restful sleep.
Here’s the interesting bit (for sleep geeks anyway)
According to research, the ideal ambient temperature for your sleeping environment is between 60-67 deg Fahrenheit. (15.5-19.4 deg C).
But overall body temperature consists of two ‘zones’ which both have to be satisfied to eliminate sleep disturbances:
- core temperature (regulated by the brain)
- shell temperature (influenced by external temperature)
The key, it seems is to hit the sweet spot. Neuroscientist Dr. Eus van Someren tested this in an experiment using thermosuits. The suits made subtle skin temperature manipulations to patients while they slept. These small adjustments Someren found, made a significant improvement in sleep quality.
While a dip in core temperature before bedtime flips on your brain and body’s “time for bed” switches and helps you fall asleep, Someren’s research shows that keeping your skin temperature “perfectly comfortable” is important when it comes to maintaining deep, restful slumber.
So what has all this got to do with feet?
It turns out that your feet are perfect for regulating external temperature. Natalie Dautovitch Professor of chronopsychology explains that your feet:
contain specialized vascular structures that help with heat loss. Specifically, the hands and feet contain blood vessels called the arteriovenous anastomoses, which — coupled with the lack of hair on the bottoms of your feet — are perfectly designed to help dissipate body heat.
Hence it turns out that sleeping with one, or both feet out of the covers is an amazingly useful life-hack to improve the quality of your sleep.