Best Fully Active B Complex is a full-spectrum B vitamin supplement, carefully designed for optimal absorption and utilization. This formulation provides the B vitamins in their safest, best tolerated, and most biochemically active forms. Thiamin (“Vitamin B1”) is fundamental to human metabolism because it is essential for the metabolism of oxygen. The microscopic “power plants” of our cells (mitochondria) require thiamin to generate energy. Riboflavin (“Vitamin B2”) is a cofactor for various mitochondrial enzymes and therefore essential for the body to make energy. Riboflavin is a necessary cofactor for the metabolism of homocysteine, a normal product of metabolism that can become toxic as it accumulates; and for the utilization of glutathione, a major antioxidant. Riboflavin also supports important enzymes that recycle folate and activate vitamin B6. Niacin and Niacinamide (“Vitamin B3”). This vitamin is fundamentally essential for numerous enzymes that make and use energy. Both niacin and niacinamide are readily activated to the cofactors that power these enzymes. Vitamin B6 (as pyridoxine hydrochloride and pyridoxal-5-phosphate). This vitamin is essential for at least 112 enzymes that metabolize carbohydrates, amino acids, and fatty acids—some 3% of all the known human enzymes. It is also essential for routing potentially harmful homocysteine along the “trans-sulfuration” pathway to produce glutathione and other important sulfur antioxidants. Vitamin B6 is vital for early brain development and for the metabolism of various brain chemical transmitters. Nerve cells both in the brain and elsewhere in the body rely heavily on B6. Certain neuroleptic drugs may impair the brain’s B6 utilization and increase dietary B6 requirements. Folate (as methyl-tetra-hydro-folate or MTHF, Quatrefolic®). This vitamin is a major dietary source of methyl groups, which are essential for a number of enzymes that make DNA, repair damaged DNA, and regulate gene activity via epigenetic actions. Folate’s central importance for such “housekeeping” functions make it crucial to the health of all our cells, tissues, and organs. Folate is also crucial for a healthy pregnancy. Vitamin B12 (cobalamin), as methylcobalamin (methyl-B12). This vitamin works very closely with folate to support methyl metabolism and recycle homocysteine. The absorption of B12 from foods is highly dependent on a healthy gastrointestinal tract, is highly vulnerable to many over-the-counter and prescription medications, and tends to decline with age. Biotin This B vitamin is incorporated into the molecular structure of at least five enzymes called carboxylases that are widely involved in energetics, fat metabolism, and the metabolism of branched-chain amino acids important for many protein functions. Mitochondria require biotin for their energy functions (together with all the other B vitamins).