Why the choline source matters
Choline supplements differ in how much elemental choline they carry and in how readily that choline reaches the brain. Choline bitartrate and the choline in lecithin (phosphatidylcholine) are inexpensive and useful for general choline status, but they are generally considered less efficient at raising brain choline. Alpha-GPC (alpha-glycerophosphocholine) and CDP-choline (citicoline) are the forms most often highlighted for cognitive use because they are well absorbed and able to cross the blood-brain barrier.
How the four forms tend to rank
By percentage of usable choline by weight, alpha-GPC is high (roughly 40 percent), CDP-choline is moderate (around 18 percent and it also yields cytidine), choline bitartrate is moderate but less brain-directed, and lecithin is the most dilute. For brain delivery the common ordering places alpha-GPC and CDP-choline ahead of bitartrate and lecithin, though individual goals differ since lecithin and bitartrate still serve whole-body choline needs.
These rankings come from pharmacokinetic and small clinical studies, not definitive head-to-head outcome trials. This is general educational information, not medical advice. Excess choline can cause side effects, so consult a qualified professional about appropriate intake.