Prevention of eating disorders with single session interventions: Hype or promise?

Is reducing the risk of eating disorders with single session interventions a hype or a promise? Tracey Wade at the Flinders University Institute for Mental Health and Wellbeing investigates

What is a single session intervention?

Single session interventions (SSIs) are brief, structured, goal-oriented programs, following evidence-based approaches to create meaningful change to mental health in a single encounter.

What evidence supports SSIs?

An umbrella review of 24 systematic reviews and meta-analyses of SSIs was published between 2007 and 2024. ⁽¹⁾ Only seven included trials of digital or paper-based self-guided SSIs; the remainder focused on face-to-face interactions. Overall, SSIs showed a small, significant positive effect across outcomes and age groups.

Compared to anxiety, depression and substance use, the evidence supporting SSIs for disordered eating is sparse: only two of the systematic reviews included in the umbrella review included studies evaluating eating problems, and only one reported positive effects in adolescents and adults.

What is the rationale for use in the prevention of eating disorders?

So far, insufficient evidence exists to support the use of unguided digital SSIs in the prevention of disordered eating. The rationale for further investigation, however, does exist, as shown in the Figure. Significantly, SSIs may successfully decrease dietary restriction, a key risk factor for the development of disordered eating. Dietary restriction refers to consciously trying to cut back the overall amount eaten to influence shape or weight.

Two studies show a decrease in dietary restriction after completing a SSI. One showed a reduction in restrictive eating in depressed adolescents at three-month follow-up compared to a control condition when either completing a SSI on Behavioural Activation (doing activities that are considered pleasant or display some mastery) or an introduction to the brain and a lesson on neuroplasticity. ⁽²⁾ The second showed a decrease in dietary restriction in adults (mean age of 27.99 years) seeking treatment for an eating disorder, using adapted versions of the two SSIs from the previous study ⁽³⁾ (shown in figure 1).

What questions need to be answered?

A variety of questions that need to be addressed in terms of the usefulness of SSIs for the prevention of eating disorders are listed in table 1. ^(4,5)

Our current research

Our research, funded by a National Mental Health and Research Council Investigator Grant (2025665), has developed nine SSIs on a smartphone app. We consulted young people and members of our Expert Advisory Group (people with lived experience, significant others, and clinicians and researchers specialising in eating disorders) to ensure that the content and features were as engaging as possible. ⁽⁶⁾

Young people aged 14–25 years old with elevated weight concern will be randomised to one of nine SSIs tackling risk factors for disordered eating or a control condition. The content of each SSI is described below. This important research will help better understand the role SSIs can play in reducing the risk of eating disorders in youth.

References

1. Schleider JL, Zapata JP, Rapoport A., et al. (2025). Single-Session Interventions for Mental Health Problems and Service Engagement: Umbrella Review of Systematic Reviews and Meta-Analyses. Annual Review of Clinical Psychology, 21(1), 279–303.
2. Schleider JL., Mullarkey MC, Fox KR, et al. (2022). A randomized trial of online single-session interventions for adolescent depression during COVID-19. Nature Human Behaviour, 6(2), 258–268.
3. Wade TD, Waller G. (2025). Transdiagnostic single session interventions identify rapid versus gradual responders and inform therapy personalisation before commencing therapy for eating disorders. Cognitive Behaviour Therapy.
4. O’Dea B & de Valle MK. (2025). Trial, Error, and Insight: Using the Pilot Study of the HOPE Program to Inform Next Steps for Digital Single-Session Research for Eating Disorders. International Journal of Eating Disorders, 10.1002/eat.24487.
5. Thompson M, Radunz M, Wade TD, Balzan RP. (2024). Bridging the gap: Can single session interventions help enhance mental health treatment delivery for young people in Australia? Australian & New Zealand Journal of Psychiatry, 58(10):829-830.
6. Pellizzer ML, Pennesi J-L, Radunz M, Zhou Y, Wade TD. (2025). Piloting single session interventions in a sample of weight-concerned youth: Study protocol for a randomised controlled trial. Body Image, 54, 101945.