Enduring eating disorders can raise difficult questions about treatment. What should providers consider when a patient has tried several approaches without lasting improvement? How can care remain responsive to the person’s needs without assuming that recovery is no longer possible?
A systematic review published in September 2026 offers useful insight. The review found that the length of time someone has had an eating disorder did not consistently predict treatment outcomes. Adults with longstanding and severe eating disorders can experience meaningful improvement. However, the evidence remains limited and no single approach has been shown to work best for everyone (Ayton et al., 2026).
For providers, the findings offer a reason to look closely at the care a patient has received, the support they need now, and what might need to change.
What the research found
Ayton et al. (2026) reviewed treatment studies involving adults with longstanding and severe eating disorders. Their review included 17 empirical studies reported across 20 publications, along with eight case studies. It is important to note that most participants had anorexia nervosa, and relatively few studies used randomized controlled designs. The researchers examined several approaches, including inpatient treatment, enhanced cognitive behavioral therapy (CBT-E), nutritional rehabilitation, outpatient treatment, digital support, medication, and other interventions.
The most consistent evidence of improvement came from intensive, integrated treatment pathways. These combined psychological treatment and nutritional rehabilitation with continuity across levels of care. Studies reported improvements in eating disorder symptoms, weight, psychological well-being, and daily functioning.
The findings need to be interpreted with consideration of individual case. The studies varied in quality, treatment approach, and how they defined longstanding illness. Many relied on observational data, and the research largely focused on women with anorexia nervosa. More studies are needed to understand which treatments work best for different patients and how well improvements are maintained over time
That being said, the main takeaway is that a longer history of illness does not, by itself, mean treatment cannot help.
When treatment has not led to lasting improvement
When a patient has experienced an eating disorder for many years, it can be useful to revisit what previous treatment involved.
Providers might consider:
- Has treatment addressed both medical and psychological needs?
- Has the level of care been appropriate to the patient’s current presentation?
- Have treatment goals and approaches been reviewed when progress has stalled?
- Have transitions between providers or treatment settings been coordinated?
- Are practical barriers making it difficult for the patient to participate in care?
The purpose is not to suggest that a different approach will guarantee improvement. It is to make sure that previous treatment experiences do not become the only basis for decisions about future care.
What providers can take from the evidence
Research on longstanding eating disorders is still developing, but several considerations are relevant to practice:
- Look beyond the length of illness. Duration alone does not establish whether a patient can benefit from further treatment.
- Review previous care. Consider what has been tried, what helped, what did not, and whether important needs remain unaddressed.
- Coordinate across disciplines. Medical, nutritional, and psychological needs may require input from several providers.
- Plan for transitions. Follow-up and continuity of care matter when patients move between treatment settings.
- Include the patient’s priorities. Clinical outcomes matter, but so do functioning, quality of life, and the person’s own goals.
- Continue to assess risk. A longstanding illness does not remove the need for appropriate medical and psychiatric monitoring.
More research is needed, but for now, the evidence supports that the duration of illness alone is not a reason to assume that further care will not be effective.
Build Your Eating Disorder Knowledge
Providers in primary care, behavioral health, nutrition, and other specialties may work with patients whose eating disorders have persisted for years. Understanding treatment options, recognizing ongoing concerns, and knowing when to consult or refer can help providers make informed decisions.
EDPEN offers in-person eating disorder trainings and customized virtual trainings for healthcare teams. Learn more about training opportunities for yourself or your team through EDPEN.
References
Asaria, A. (2026). Care approaches for people with longstanding eating disorders: A lived experience perspective on the need for recovery-fostering care. Journal of Eating Disorders, 14, Article 237. https://doi.org/10.1186/s40337-026-01786-5
Ayton, A., Kumar, A., Downs, J., Boniface, S., et al. (2026). Treatment interventions for longstanding and severe eating disorders: An updated systematic review and narrative synthesis. Journal of Eating Disorders. Advance online publication. https://doi.org/10.1186/s40337-026-01722-7