Free and bound choline blood levels after phosphatidylcholine.

In six normal subjects we investigated the effects of oral phosphatidylcholine (lecithin) on the concentrations of plasma choline, erythrocyte choline, and choline-containing lipids. Plasma choline levels rose 1 hr after treatment and remained elevated for 8 hr, with peaks at 3 and 4 hr after phosphatidylcholine. Erythrocyte choline levels also rose, although the rise was slightly delayed relative to plasma choline. There was no change in the plasma choline-containing lipid concentration. These results demonstrate that, in normal subjects, oral phosphatidylcholine indices prolonged rises in plasma and erythrocyte choline concentrations and is therefore useful when such effects are desired.