Abstract: The present disclosure relates generally to genes and biological pathways involved in the active regulation by mood and stress of life expectancy, in all subjects, and separately by gender. Some of these represent a life switch between suicide and longevity. Disclosed are methods for identifying compounds involved in the modulation of active longevity by mood and stress, in particular compounds that modulate the life switch, and thus, modulate active longevity. Also disclosed are methods for increasing active longevity in a subject in general, and modulating the life switch in a subject with psychiatric disorders in particular. Also disclosed are methods for determining biological age score in a subject in general, and predicting lifespan/time to death from all causes in subjects.