is especially predictive of living a longer life--

Researchers studied the link between biological markers of health, including body mass index, waist circumference, blood markers (A1c, HDL cholesterol, etc.), physical performance (lung function, grip strength, walking speed) and correlated facets that constitute the conscientiousness trait (self-control, order, industriousness, traditionalism, virtue, and responsibility).
 

Results showed that “four of the six facets of conscientiousness were associated with nearly all of the health markers." Higher conscientiousness predicted "healthier metabolic, cardiovascular and inflammatory markers, and better performance on physical assessments.”