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Drinking Hot Spring Water (Insatsu) | What It Is, Benefits & Safety Rules

Published May 6, 2026·1min read

Insatsu — drinking hot spring water directly — has a long history in Japan and Europe. Certain spring types are recognised to support digestive and metabolic health, but the practice is strictly regulated and must be done at authorised facilities only.

Table of Contents
  1. What Is a Licensed Drinking Spring?
  2. Recognised Benefits of Drinking Spring Water
  3. Who Should Not Drink Spring Water

What Is a Licensed Drinking Spring?

Under Japan's Hot Spring Act (Article 14), only facilities holding a designated "drinking use permit" (飲用許可) may offer insatsu. These facilities are required to post information on the spring type, recommended quantity, and contraindications near the drinking point. Drinking unlicensed spring water directly is prohibited and may pose health risks due to high mineral concentrations.

Recognised Benefits of Drinking Spring Water

  • Constipation & impaired digestive function (chloride springs, sulfate springs)
  • Anaemia (iron-containing springs)
  • Gout — urine alkalinisation (bicarbonate springs)

Who Should Not Drink Spring Water

  • Facilities without a drinking permit (never drink unlicensed spring water)
  • Infants and young children
  • Persons with impaired kidney function (especially radon springs)
  • Pregnant women (especially sulfur springs)

BEST SPRINGS FOR DRINKING

Drinking-Friendly Onsen (Carbonated Spring)

Find facilities across Japan offering drinkable Carbonated Spring water.

※ Only drink onsen water where official permission and instructions are clearly posted.

TRY IT NOW

Find This Onsen on the Map

References

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