Folic acid (Vitamin B9)

Folic acid is the synthetic form of Vitamin B9, a water-soluble vitamin that the human body cannot produce on its own. While 'folate' occurs naturally in foods like leafy greens and legumes, 'folic acid' is the version used in dietary supplements and mandatory food fortification programs (such as enriched flour and cereal) due to its superior stability and higher bioavailability—roughly 85% compared to only 50% for food-sourced folate.