Each capsule provides 400 mg of L-alpha-Glycerophosphorylcholine (Alpha GPC) at 99% purity. Alpha GPC is the most bioavailable form of choline it crosses the blood brain barrier efficiently and serves as a direct precursor to acetylcholine, the primary neurotransmitter of the cholinergic system involved in memory, learning, and attention. Why Purity Matters Alpha GPC is hygroscopic and commercially available in 50% and 99% purity grades. The 50% form uses silica or other carrier materials as roughly half the weight meaning a 400 mg label dose at 50% purity delivers only ~200 mg of actual Alpha GPC. This formula uses 99% purity Alpha GPC, so 400 mg on the label is 400 mg of L-alpha-Glycerophosphorylcholine. When comparing alpha GPC supplements, verify both the stated dose and the purity grade. How Alpha GPC Works Alpha GPC is a phospholipid bound form of choline found naturally in the brain. As a choline source, it crosses the blood brain barrier and is cleaved to release free choline directly in the CNS. That choline is used by choline acetyltransferase (ChAT) to synthesize acetylcholine. Acetylcholine is essential for attention, learning, memory formation, and memory retrieval. Alpha GPC also contributes to phosphatidylcholine synthesis, supporting neuronal membrane integrity.
