The impact of a brief gratitude intervention on subjective well-being, biology and sleep

This randomised controlled experiment tested whether a brief subjective well-being
(SWB) intervention would have favourable effects on cardiovascular and neuroendocrine
function and on sleep. We compared 2 weeks of a gratitude intervention with an active
control (everyday events reporting) and no treatment conditions in 119 young women.
The treatment elicited increases in hedonic well-being, optimism and sleep quality along
with decreases in diastolic blood pressure. Improvements in SWB were correlated with
increased sleep quality and reductions in blood pressure, but there were no relationships
with cortisol. This brief intervention suggests that SWB may contribute towards lower
morbidity and mortality through healthier biological function and restorative health
behaviours.