During self-regulatory effort, a series of potentially energy-saving changes occur in the heart and immune system. The present study tested the possibility that one function of the liver, alcohol metabolism, also slows in the presence of self-regulatory effort. Young men (N=19) received a small dose of alcohol and performed either self-regulatory tasks or identical tasks without a self-regulatory component, counterbalanced across two sessions. There was no main effect of condition on alcohol metabolism; however, trait self-control moderated the effect of condition such that those with higher trait self-control metabolized alcohol at similar rates across conditions, whereas those with lower trait self-control experienced a slowing of alcohol metabolism in the high self-regulation condition compared with the low self-regulation condition. This finding adds changes in liver metabolism to the "pause and plan" profile of self-regulation and suggests that trait self-control reduces the effort associated with self-regulatory tasks.