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SODIUM

Sodium ion: Main Effects & Top 5

Published May 5, 2026·1min read

Sodium ion (Na⁺) is the key component of chloride and bicarbonate springs. It forms a thin salt film on the skin, locking in warmth long after bathing.

National maximum
2729.0 mg/kg
@
Shijo Kawaramachi Onsen Soraniwa Terrace Kyoto Bettei
Table of Contents
  1. What is Sodium ion?
  2. Main Effects
  3. Sodium ion Top 5 Hot Springs

What is Sodium ion?

Sodium ion (Na⁺) is the key component of chloride and bicarbonate springs. It forms a thin salt film on the skin, locking in warmth long after bathing.

Main Effects

  • Post-bath heat retention
  • Relief from poor circulation
  • Skin hydration

Sodium ion Top 5 Hot Springs

Top 5 hot springs registered on this site with the highest content.

* Top 5 among onsen analysis records registered in this app

References

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