Findings from the Yamagata study suggest that laughter may be associated with decreased risk of cardiovascular disease and all-cause mortality. The study included 17,152 subjects all over 40 years old who participated in an annual health check where they self-reported daily frequency of laughter. The patient follow-up occurred over a median of 5.4 years during which time 257 subjects died and 138 experienced cardiovascular events. Statistical analysis was adjusted to reflect age, gender, history of hypertension, smoking and alcohol use and showed that all-cause mortality was significantly higher in those who laughed less than once per month than those that laughed more than once per week. Similarly, risk of cardiovascular events was higher in subjects who laughed ≥1 time/month but <1 time/week than in subjects who laughed ≥1 time/week.