Acceptance Therapy Shows Real Promise Against Insomnia, Landmark Analysis Finds

For millions of people lying awake at 3 a.m., trapped in a spiral of frustration about their own sleeplessness, a new scientific analysis offers a striking message: the battle against insomnia may be won not by fighting harder, but by letting go. A comprehensive updated meta-analysis of randomized controlled trials, published in the Journal of Clinical Sleep Medicine, has found that acceptance and commitment therapy, a psychological treatment better known by its acronym ACT, produces moderate-to-large improvements in insomnia symptom severity compared with waitlist or standard control conditions. The findings, drawn from a rigorous synthesis of trials registered across PubMed, Embase, and the Cochrane Library, position ACT as a credible alternative to the current gold standard treatment, cognitive behavioral therapy for insomnia, or CBT-I, while simultaneously confirming that the older therapy retains its crown.

The research team, led by Douglas Barroso of the State University of Santa Cruz in Brazil together with co-senior authors Daniel B. Kay of Brigham Young University and Renatha El Rafihi-Ferreira of the University of São Paulo, set out to answer a question that has grown increasingly urgent as insomnia rates climb worldwide. Insomnia disorder, defined by persistent difficulty falling or staying asleep despite adequate opportunity for sleep, affects a substantial proportion of adults across cultures and carries enormous societal costs, from lost productivity to elevated risks of depression and even suicidal behavior. Previous epidemiological surveys in England documented rising insomnia prevalence and increased use of hypnotic medications over fifteen years, underscoring the need for effective, accessible, non-pharmacological treatments.

CBT-I has long been the first-line recommendation in clinical guidelines from the American Academy of Sleep Medicine and the European Sleep Research Society. Its efficacy is well established across dozens of trials and multiple meta-analyses, including studies showing benefits even when insomnia is comorbid with psychiatric and medical conditions or chronic disease. Yet CBT-I has a practical weakness: its core behavioral components, particularly sleep restriction therapy, which deliberately compresses time in bed to rebuild sleep drive, can be demanding and uncomfortable for patients. Research on patient experience has shown that adherence to sleep restriction is a genuine barrier, and studies of treatment-seeking behavior reveal that many people with insomnia never pursue therapy at all. This is where ACT enters the picture with a fundamentally different philosophy.

Acceptance and commitment therapy, developed from the framework of contextual behavioral science, does not attempt to eliminate unwanted thoughts or sensations directly. Instead, it targets experiential avoidance, the struggle to control or escape difficult inner experiences, and cultivates psychological flexibility through acceptance, mindfulness, values clarification, and committed action. Applied to insomnia, ACT encourages patients to stop waging war against wakefulness. Rather than lying in bed monitoring the clock and catastrophizing about tomorrow, patients learn to observe sleep-related thoughts without acting on them and to redirect energy toward what matters in their lives regardless of how a given night unfolds. A influential metacognitive model of insomnia published by Ong, Ulmer, and Manber in 2012 provided the theoretical foundation for this approach, arguing that the effortful struggle to sleep is itself a maintaining factor of the disorder.

To test how well this philosophy translates into clinical outcomes, the researchers conducted a systematic review and meta-analysis following Cochrane Handbook guidance and PRISMA 2020 reporting standards, assessing risk of bias in included trials with the revised RoB 2 tool. They searched three major databases for randomized controlled trials comparing ACT or ACT-based interventions against non-ACT conditions in patients with insomnia. Continuous outcomes were pooled using a restricted maximum likelihood random-effects model in the statistical environment R, a method that accounts for heterogeneity between studies while producing robust combined estimates. The trials encompassed a range of delivery formats, including face-to-face individual and group therapy, telehealth programs enhanced with ACT principles, and internet-delivered self-help interventions for subclinical and clinical insomnia.

The headline result was unambiguous. Compared with waitlist or standard control conditions, ACT produced a standardized mean difference of minus 0.67 in insomnia symptom severity, with a 95 percent confidence interval of minus 1.08 to minus 0.25, a moderate-to-large effect by conventional statistical conventions. In practical terms, patients receiving ACT reported substantially reduced insomnia severity on validated instruments such as the Insomnia Severity Index. Perhaps even more striking were the effects on psychological wellbeing: ACT yielded a small-to-moderate reduction in depression symptoms, with a standardized mean difference of minus 0.34, and a comparable reduction in anxiety symptoms, at minus 0.42, both statistically significant. These secondary outcomes matter enormously, because insomnia and mood disorders are deeply intertwined, with longitudinal evidence suggesting primary insomnia is a risk factor for developing depression.

The direct comparison with CBT-I told a more nuanced story. At posttreatment, there was no significant difference in insomnia severity between the two therapies, with a standardized mean difference of 0.21 favoring CBT-I but with a confidence interval of minus 0.02 to 0.43 that crossed the null. At six-month follow-up the gap narrowed further to a non-significant 0.14. Treatment response rates, defined as a reduction of more than seven points on the Insomnia Severity Index, also did not differ significantly between the therapies. However, one metric did separate them: CBT-I produced significantly higher remission rates at posttreatment, defined as an Insomnia Severity Index score below 8, with a relative risk of 0.81 for ACT, meaning ACT patients were somewhat less likely to achieve full remission by that strict threshold. By follow-up, even this advantage had dissolved into statistical equivalence, with a relative risk of 0.78 and a wide confidence interval of 0.47 to 1.29.

The authors interpret these findings with careful balance. ACT, they conclude, can be an efficacious treatment for insomnia, with particularly strong outcomes for the psychological symptoms that so often accompany sleepless nights. Nevertheless, CBT-I remains the gold standard due to its more extensive and consistent evidence base. This distinction between efficacy and evidentiary maturity is crucial for clinicians and policymakers. CBT-I has accumulated decades of trial data, dose-response evidence showing that more sessions yield better outcomes, and demonstrated effectiveness across primary care settings, group formats, telephone consultations, and digital platforms. ACT for insomnia, by contrast, rests on a smaller but rapidly growing foundation, including recent head-to-head randomized trials in chronic insomnia patients, comparative effectiveness research in women veterans, and pilot studies combining ACT with bedtime restriction.

The implications for clinical practice are nonetheless significant. If ACT matches CBT-I on symptom severity and outperforms it on durability of remission advantage over time, while additionally delivering meaningful relief from depression and anxiety, it offers clinicians a genuine choice in tailoring treatment. Patients who find the demanding behavioral prescriptions of CBT-I unpalatable, or who present with prominent comorbid mood symptoms, may be better suited to an acceptance-based approach. The growing menu of ACT delivery formats, from internet-based self-help to telehealth, also speaks to the pressing problem of treatment access, since most people with insomnia never receive any evidence-based psychological care. As the field moves toward personalized sleep medicine, this updated meta-analysis provides the strongest evidence yet that teaching patients to accept the night, rather than conquer it, is a scientifically legitimate path to better sleep.

Subject of Research: Efficacy of acceptance and commitment therapy compared with cognitive behavioral therapy for insomnia

Article Title: Acceptance and commitment therapy for insomnia: an updated meta-analysis of randomized controlled trials

Article References: Barroso, D., de Paula Portilho, N., Garbacka-Struzik, A., Godoi, D. C., Ellwanger, M. P., Pereira Mendes, T., Alves Ribeiro, V. E., Soares, V. G., Hespanhol, L. C., Siegloch, M. L., Zahran, I. R., Stadler de Abreu, V., de Oliveira, H. M., Peluffo, B., Cerchi, E., Kay, D. B., & Rafihi-Ferreira, R. E. (2026). Acceptance and commitment therapy for insomnia: an updated meta-analysis of randomized controlled trials. Journal of Clinical Sleep Medicine, 22(1), Article 132. https://doi.org/10.1007/s44470-026-00125-4

Image Credits: AI Generated

DOI: 10.1007/s44470-026-00125-4

Keywords: acceptance and commitment therapy, ACT, insomnia, CBT-I, cognitive behavioral therapy, meta-analysis, randomized controlled trials, sleep medicine, psychological flexibility, depression, anxiety, Journal of Clinical Sleep Medicine