Why It's A Tradition In Japan To Drink Milk After A Onsen Bath

News about Japan can be peppered with accounts of earthquakes both big and small, which is not surprising given that the country has over 100 active volcanoes — more than any other country in the world, per Volcano Discovery. And while that fact might give visitors some pause for thought, it's also given the country and its residents an unexpected — and delightful — side benefit: easy access to onsen.

Onsen, or hot springs, are everywhere in Japan and have become a must-do for people who live or visit the country. They are usually warmer than 25 degrees Celcius (77 degrees Fahrenheit), often hovering around 100 degrees Fahrenheit, according to Live Japan, and contain at least one of 19 minerals including iron, sulfur, and lithium. JAL's Guide to Japan says the country has two types of onsen: man-made, and natural, whose waters are supplied by geothermal springs. Soaking in natural hot springs — or "toji" — has the effect of improving blood circulation, naturally lowering stress levels, helping to manage muscle pain and aching joints, and dealing with a host of skin conditions.

Inside Japan Tours tells visitors to expect a few practices to follow before chilling in an onsen: bathing is only permitted in the nude — which is why private rooms are available for the more modest; onsen bathers need to shower before and after going into the water; hair must be put up in a cap or towel; and then there's the après bath experience of having a bottle of milk.

Enjoy Onsen says an explanation to the practice of drinking milk after a turn in the hot springs depends on who you ask. One version refers to two enterprising businessmen Ken Moriyama and Sumida Shokai who decided to get together to expand sales of their individual products, milk and coffee. They created a beverage called "coffee milk" which took off in the 1940s. Another version talks about another dairy producer who had wanted to sell milk but decided to do so at bathhouses, where refrigerators could be commonly found, and the practice was born.

Today, Live Japan shares onsen bathers have a choice of coffee milk or fruit milk — both are sweet drinks that seem to help the body re-energize quickly after a bath. The site says bathers also have another option: a sweet, fizzy carbonated water drink known as "Teppo Water Cider," which is closer in flavor and composition to Sprite, per Japan Travel.