The key to getting a good night’s sleep may lie in the cooling down of – YUYU EU

The key to getting a good night’s sleep may lie in the cooling down of our bodies and the temperature of our bedrooms

Sleep experts give an in-depth look at how temperature affects the quality of sleep and how the YUYU Bottle may be the secret to helping you get a good night’s rest.


Pictured: YUYU Bottle in the Belgian Pimlico in Sand Linen

We often hear one of the ways of getting a good night's sleep is taking a warm shower or bath before bedtime as well as making sure the temperature of the bedroom is cool. But have you wondered why that was the case? As a company that focuses on providing warmth and comfort to our customers, we wanted to delve into the science behind how the temperature of our bodies and the environment affects our sleep. 


"Hot baths actually work...for the opposite reason that most people think"

In an interview published on NPR, Matthew Walker, a neuroscientist and sleep specialist at the University of Berkeley and author of Why We Sleep says the following,

"We know that your core body temperature needs to drop by about 2 to 3 degrees Fahrenheit to initiate good sleep and then maintain deep sleep."

"The way it works is this: For you to get your heat out of the core of your body, you actually need to release that core heat through the outer perimeter surfaces of your body, namely your hands and your feet. And this is why hot baths actually work ... for the opposite reason most people think."

"You are essentially like a snake charmer — you are charming the heat out of the core of your body to the surface of your body."

"You get into a hot bath, you get out, you think I'm nice and toasty, I get into bed and I fall asleep better because I'm warm. The opposite is true. What happens with a bath ... is you actually bring all of the blood to the surface. And your hands and your feet are wonderful radiators of that heat. So you are essentially like a snake charmer — you are charming the heat out of the core of your body to the surface of your body."


A study published in the Sleep Medicine Reviews found that,

"A bath or shower of about 40 degrees Celsius (104 degrees Fahrenheit) before bedtime that lasted for as little as 10 minutes was significantly associated with improved sleep quality, and increased the overall amount of time slept. In at least a couple of studies, taking a bath one or two hours before bedtime decreased the average amount of time it took the study participants to fall asleep — by about nine minutes."

Next time you experience troubles falling asleep, hop into your shower or bath for a nice warm soak to get your body relaxed for some shut-eye. zzz


A cool room temperature — one of the most important factors in getting a good night’s sleep

While we may prefer a hot day at the beach, sleeping in tropical temperatures may not be conducive to sleep. According to the National Sleep Foundation, the best optimal bedroom temperature is 18.3 Celsius (65 degrees Fahrenheit). While this may vary from person to person, keeping the thermostat set between 15.6 to 19.4 degrees Celsius (60 to 67 degrees Fahrenheit) helps provide a comfortable sleeping environment.

Why so low? Here's what the experts had to say.

Our bodies are programmed to experience a slight dip in core temperature in the evening. Turning the thermostat down at night may help with temperature regulation and signal your body that it’s time for bed.”

"Warmer temperatures cause discomfort and restlessness which interfere with your body's thermoregulation abilities and cause fatigue which results in an inability to fall asleep."

"Body temperature affects not only sleep onset but also sleep quality and the time spent in different sleep stages. A higher core body temperature has been associated with a decrease in restorative slow-wave sleep and subjective sleep quality. Similarly, a bigger difference in temperature between the core and the extremities – which indicates that the body is not efficiently sending heat away from the core – has been associated with decreased sleep efficiency and a higher likelihood of waking up after falling asleep.”


Optimise your sleep routine with YUYU

Pictured: YUYU Bottle in the Belgian Pimlico Linen in Rose

The National Sleep Foundation also offers some tips when it comes to keeping the bedroom cool. During the hot months they recommend the following: 

  • Moving downstairs where the temperature is cooler
  • Keeping the blinds closed to reduce heat build-up during the day
  • Using a fan or AC in hot climates, a hot water bottle on cold nights
  • Opening the windows to promote air circulation/ventilation

The YUYU Bottle is an ideal bedtime accessory to cool you down during those hot nights. Our hot water bottle is unique from other hot water bottles not only for its design and shape but because it can be used for both warm and cold use.

All it takes is 5 easy steps

  1. Before each use, check the YUYU rubber bottle and stopper for any wear or damage. If you see any damage, stop use immediately.
  2. Pour water 1/2- 3/4 way into the YUYU rubber bottle. Avoid filling all the way to the top as it may expand and stretch the bottle. 
  3. Expel any excess air from the YUYU rubber bottle. Secure the stopper finger-tight to prevent leakage. 
  4. Place the YUYU rubber bottle into the freezer for 3-5 hours (or until you feel it is frozen enough). Note: The time it takes to completely freeze will vary depending on the freezer you are using.
  5. Take the YUYU rubber bottle out of the freezer and gently place it into the cover and bring it with you to bed.

The elongated shape of the YUYU Bottle gives you double the surface area coverage for a full-body cool down, keeping your body and your bedsheets cool all throughout the night.


The ultimate bedtime accessory that instantly relaxes you and gives you warmth from head to toe

Pictured: YUYU Bottle in the Richmond Cashmere & Merino Blend

The YUYU Bottle can also be used for its traditional use of keeping you warm on those chilly nights. The signature long hot water bottle helps to keep your body warm but can also help with warming your bedsheets and your toes, giving you warmth from head to toe. 

Please note: it is strongly recommended to separate your warm and cold use as it may weaken the rubber bottle. Head to our Accessories page to purchase a separate YUYU Bottle. 





A Warm Bedtime Bath Can Help You Cool Down And Sleep Better

Before-bedtime passive body heating by warm shower or bath to improve sleep: A systematic review and meta-analysis

The Best Temperature for Sleep

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