A meta-analysis of the effects of written emotional disclosure on the health outcomes of clinical populations
Writing about difficult experiences produced a small but statistically significant improvement in the health of people with physical or psychiatric conditions, d = 0.19. The benefit was clearly larger for physical health outcomes (d = 0.21) than psychological ones (d = 0.07).
Writing helped the body more than the mind - which is not the story usually told about journaling.
Frisina and colleagues pooled nine studies of the written emotional disclosure paradigm in people living with physical or psychiatric disorders. Overall, expressive writing significantly improved health, d = 0.19.
A planned contrast then split the result: expressive writing was more effective on physical outcomes (d = 0.21, p = .01) than on psychological ones (d = 0.07, p = .17, not significant).
Note the size. d = 0.19 here sits almost exactly where the 2025 gratitude meta-analysis landed at g = 0.19 - two different literatures, two decades apart, arriving at the same modest magnitude. That convergence is worth more than any single dramatic study.
The authors are candid that small, heterogeneous samples may explain the small effect, and they call for randomised controlled trials.
The psychological effect was not statistically significant on its own, which is the opposite of what most people assume writing does. It pools only nine studies with small, heterogeneous samples, and the authors themselves call for randomised controlled trials to test the effect properly.
Summarized by Tiago Martins · Last updated: · How we write these
