MINERALS

Manganese ion: Main Effects & Top 5

Published May 5, 2026·1min read

Hot springs containing manganese ion (Mn²⁺) at ≥ 10 mg/kg are rare in Japan. This trace element keeps the stratum corneum supple and supports the skin's antioxidant defense.

Table of Contents

What is Manganese ion?
Main Effects
Manganese ion Top 5 Hot Springs

What is Manganese ion?

Hot springs containing manganese ion (Mn²⁺) at ≥ 10 mg/kg are rare in Japan. This trace element keeps the stratum corneum supple and supports the skin's antioxidant defense.

Main Effects

Keeps the stratum corneum suppleManganese is a trace element that supports the metabolic processes of keratinocytes, the cells that form the skin's outer layer. This action may help refine skin texture and maintain the natural flexibility of the stratum corneum.
Antioxidant action as an SOD cofactorManganese acts as a cofactor for superoxide dismutase (SOD), an enzyme that neutralizes harmful free radicals. This function helps to alleviate oxidative stress on the skin, protecting it from cellular damage.
Found in very few hot springs nationwideAccording to Japan's Ministry of the Environment guidelines, a spring must contain at least 10 mg/kg of manganese ions (Mn²⁺) to be officially recognized for this component. Hot springs that meet this standard are exceptionally rare across the country.

Manganese ion Top 5 Hot Springs

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

RANKING BY THIS MINERAL CONTENT

References

MINERALMay 5, 2026· 1min read

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Iron(II) ion (Fe²⁺) is the marker of iron-rich springs. The water turns yellow-brown to red-brown when exposed to air, offering strong heat retention.

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Strontium ion (Sr²⁺) is a rare trace element with calcium-like properties. Its gentle astringent action tightens the skin.

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Metasilicic Acid: The "Beauty Spring" Standard Mineral & Top 5 Onsen

Metasilicic acid (H₂SiO₃) is a natural moisturizer also found in skincare lotions. Hot springs containing more than 50mg/kg are called "beauty springs" — leaving skin hydrated long after bathing. This is one of the therapeutic spring criteria in Japan's Mineral Spring Analysis Guideline (Table 1-1).