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- Onsen & Sentō — Everything you need to know about hot water
Onsen & Sentō — Everything you need to know about hot water
History, culture, health benefits, and art of onsen & sentō in Japan.
The first time I went to Japan was in 2011 and quickly got accustomed to hot baths.
In 2013, I traveled around the southwest of England and when I visited a friend in Bristol, I decided to visit Bath and its famous hot thermal bath.
Excited at the idea of having a nice hot bath, my spirit was quickly crushed by discovering they were cooling the water so low it was almost cold.
My experience in Bath was not even lukewarm.
Fast forward to this year.
I recently watched Yudō: The Way of the Bath on the plane. It’s a 2022 Japanese comedy movie about bathing culture.
The love of bathing is taken to the extreme to make it funny, but the movie is still really good at showing why Japanese people love baths.
And it made me want to know more about why it’s so prominent.
There’s one obvious answer: Japan has the largest amount of hot spring sources in the world. There are around 27,000 hot springs!
A word for hot water
Hot water is so culturally important that it has its own word and character!
湯 (yu) is the word for hot water (the movie I referenced starts with this character)
水 (mizu) is the word for fresh water
And to understand the rest of this newsletter, here are 3 words related to baths:
温泉 (onsen) is the word for natural hot springs
銭湯 (sentō) is the word for bathhouses
お風呂 (ofuro) is the word for bath in general
Health benefits of hot water
Bathing in hot water during a cold winter day isn’t just pure bliss, it’s also good for your health!
Japan has countless old tales about healing severely ill people by making them drink hot water or by bathing in onsen.
And buddhism also encouraged bathing for the purpose of purification, and many temples provided public bathing facilities.
For the scientific explanation, soaking in hot water raises your body temperature and your metabolism temporarily. It reduces pressure on your body and relaxes your muscles. And sweating removes toxins. But men beware, too hot for too long and it might affect your golden balls negatively.
Rise and fall of sentō
Despite so many onsen, the closest isn’t always close enough to bath regularly.
So as cities started to grow and body cleanliness became more important during the Edo period (1603-1868), bathhouses started to pop up everywhere.
But sentō are now slowly dying out.
Homes started to have their own baths in the 20th century and the convenience of it made going to sentō bothersome.
Sentō still have 2 things home baths will never replace: community and beautiful art.
Bath and bonding
Sentō were a great 3rd place to enjoy a good time with friends and neighbors.
While they are disappearing, this bonding activity hasn’t disappeared completely because home baths are still a place to bond with your family.
You don’t bathe to clean yourself, you do that outside the bath.
You go into the bath once clean to soak in it. And in Japan, it is a family activity when kids are young.
It’s a nice way to relax with everyone at the end of a hard day.
Drinking plain hot water
I mentioned it briefly in the health benefits and while historically there are stories about it, Japanese people rarely drink plain hot water.
Drinking hot water is more of a Chinese thing.
In traditional Chinese medicine, it is believed that hot water is 陰 (yīn), which represents coolness and is necessary to counteract 陽 (yáng).
And public health campaigns have encouraged people to drink warm water.
But Japan has had a recent surge in popularity for plain hot water.
Asahi — one of the largest beer brewers in Japan — is now selling warmed-up mineral water and they said that there’s a growing demand.
I personally find water warmed up with tetsubin — a cast-iron kettle — to be a treat. The minerals of the kettle leach into the water (similarly to clay teapots) and make the water really smooth and round.
Other tidbits
Time to bathe: Everyone has its preferences. Some prefer to do it in the morning, others the evening.
Cold drinks after bath: Many sentō have vending machines selling cold coffee milk or fruit-flavored milk. It’s the best feeling after a hot bath!
Cooking food in onsen water: You can sometimes find food boiled by natural hot spring water in onsen areas. It’s usually eggs but some places offer you meals entirely made by boiling food in onsen water.
Rotenburo: Word for outdoor hot spring baths, often with scenic views. My favorite activity in a private rotenburo: s*x. 👍
Super sentō: While most sentō are pretty small, sometimes you have super sentō with lots of different baths, massage chairs, restaurants, and more.
No tattoos: Many onsen and sentō traditionally ban visitors with tattoos due to their association with organized crime. I’ve met people who got snitched and were banned!
Mt Fuji in sentō: Many sentō feature large murals of Mt Fuji on their walls. This tradition dates back to the post-war period when sentō owners sought to create a more uplifting atmosphere. Mt Fuji, as Japan's most recognizable natural landmark, became a popular choice.
Going Further
Visually Pleasing
If you want to see more beautiful photos of sentō, I recommend the website Dokodemo Sento from Stephanie Crohin, a French expert on the subject (she has written a few books on the subject).
This article from Tokyo Weekender explores the traditional Japanese patterns and the illustrations they’ve used are really beautiful
Weekly Digest
Shibuya's 2.6-kilometer greenway redevelopment project, costing 110 billion yen, is sparking debate due to expensive pink benches. Each bench costs over 4 million yen, raising concerns among locals about excessive spending. While some appreciate the design, others worry about potential issues like littering and safety.
You can buy jelly in a pouch for quick energy. I’ve recently been using them with success but the texture and taste are pretty weird.
Now there’s a new drink from the same brand claiming to reduce hunger by turning into jelly in the stomach. The texture will be better, but I’m guessing the taste is still pretty bad.
“We have won the war on floppy disks on June 28!”
The war on fax machines is still raging though. See you in 10 years when they have (maybe) won that war.
I really like the illustrations they’ve used on the 1,000 and 2,000 yen bank notes.
