Evening-lactalbuminin take caused a 130% increase in Trp:LNAA before bedtime (P0.0001) and modestly but significantly reduced sleepiness (P0.013) and improved brain-sustained attention processes (P0.002 the following morning. Only in poor sleepers was this accompanied by improved behavioral performance (P0.05).
Evening dietary increases in plasma tryptophan availability for uptake into the brain enhance sustained alertness early in the morning after an over night sleep, most likely because of improved sleep