Ten studies link hunger to reduced self-control. Higher levels of hunger-as assessed by self-report, time since last eating, or physiology-predicted reduced self-control, as indicated by increased racial prejudice, (hypothetical) sexual infidelity, passivity, accessibility of death thoughts and perceptions of task difficulty, as well as impaired Stroop performance and decreased self-monitoring. Increased rates of hunger across 200 countries predicted increased war killings, suggestive of reduced aggressive restraint. In a final experiment, self-reported hunger mediated the effect of hungry (v fed) participants performing worse on the Stroop task, suggesting a causal relationship of hunger reducing self-control.