# Fulvic Acid Bioavailability: What the Research Shows Fulvic acid, the primary bioactive compound in Shilajit, has garnered significant attention in nutritional science for its remarkable ability to enhance nutrient absorption. ## Bioavailability Enhancement Fulvic acid increased iron absorption by 43% and zinc absorption by 37% compared to standard mineral supplements. ## Molecular Size Matters The molecular weight of fulvic acid (1,000-10,000 Daltons) is optimal for biological activity, allowing it to cross the blood-brain barrier and enter cells easily.