The Effects of Self-compassion on Stress and Health Behaviours

Self-compassion has emerged as a promising psychological resource for regulating stress and supporting adaptive health behaviours, yet its dynamic role in everyday stress-behaviour processes remain incompletely understood. This thesis examined how trait and daily self-compassion function in stress processing and health behaviour engagement, and whether a brief self-compassion intervention can influence these processes in naturalistic settings.
The meta-analysis (study 1) synthesised existing evidence (k = 19 studies) linking self-compassion with stress and health behaviours. Self-compassion was found to be significantly associated with lower stress, greater engagement in health-promoting behaviours and lower engagement in health-risk behaviours. Stress partially mediated these associations, indicating that stress is involved in the processes linking self-compassion with health behaviours.
Two daily diary studies (study 2 & 3) extended this knowledge by examining fluctuations in self-compassion, stress, and multiple health behaviours and outcomes in daily life. At the between-person level, higher trait self-compassion was associated with lower daily stress and healthier eating, and better sleep-related outcomes, including reduced pre-sleep arousal and morning tiredness. At the within-person level, days characterised by higher self-compassion were linked to fewer daily hassles, more daily uplifts, greater vegetable consumption, but poorer subsequent sleep quality. Self-compassion also buffered associations between daily stress and maladaptive behaviours, particularly stress-related snacking.
Finally, a randomised controlled trial (study 4) tested whether a brief self-compassion expressive writing intervention could influence daily stress-behaviour dynamics across 7 days. The intervention significantly moderated the daily hassles-snacking, daily uplifts-snacking and daily uplifts-sleep associations, which provided initial evidence that cultivating a self-compassionate mindset can influence behavioural responses to daily emotional triggers.
Overall, this thesis demonstrates that self-compassion functions as a context-sensitive psychological resource shaping both between-person differences and within-person stress-behaviour processes. By integrating multi-method and multilevel approaches, the findings extend understanding of self-compassion in daily life and highlight the potential for low-burden, scalable interventions to support stress-related health behaviours and outcomes.