Molecular hydrogen (H2) is the lightest and smallest chemical element that exists naturally. It is a colorless and odorless gas. Hydrogen was long thought to have a negligible effect on the human body, but emerging evidence suggests that it may have therapeutic potential as a medical gas. Regardless, research on molecular hydrogen is still in its infancy. While there seems to be promise, it may be too soon to recommend molecular hydrogen for any particular purpose.
What is molecular hydrogen?
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•Last Updated: May 16, 2025
Molecular hydrogen (H₂) is a colorless and odorless gas and is the lightest and smallest chemical element. Although it was previously considered to have little effect on the human body, emerging research indicates potential therapeutic benefits, but further studies are needed before making specific recommendations.