Fulvic Acid

The low-molecular-weight fraction of humic substances — smaller, more oxygenated, and soluble at every pH, unlike humic acid, which precipitates out below pH 2. Yellow to light brown rather than dark brown/black.

Plain-Language Summary

Fulvic acid’s defining property is size: at roughly a tenth the molecular weight of humic acid, it penetrates skin and biological membranes far more readily. That single property — bioavailability — is why fulvic acid gets discussed separately from humic acid despite belonging to the same compound family and forming through the same humification process. It’s present in smaller absolute quantities than humic acid in most peat, but its higher reactivity per unit mass (more carboxyl/hydroxyl groups relative to its size) partly compensates.

What It Does

Best known as a mineral-transport molecule — its small size and high density of chelating functional groups let it bind trace minerals (iron, zinc, magnesium) and carry them across skin during balneotherapy, which is the chemical basis for “mineral delivery” as a mechanism. It also shows independent anti-inflammatory and antioxidant activity.

Where the Data Lives

This page is a plain-language orientation. For the full evidence-graded list of biological activities and the specific studies behind each claim, see Fulvic Acids.