Obesity and dietitian societies have joined forces to issue a new consensus statement on recommendations surrounding use of obesity drugs for weight loss treatment. The consensus statement is being presented at this year's European Congress on Obesity (ECO 2026) in Istanbul, Turkey, and co-authored by lead author Dr Laurence Dobbie, Department of Population Health Sciences, School of Life Course & Population Sciences, King's College London, UK as part of an international team of 26 authors.
Incretin-based therapies (IBT) such as GLP-1 receptor agonists, have transformed obesity management but may pose nutritional, functional, and psychological risks. To ensure that patients get the best and safest care while using these relatively new drugs, the European Association for the Study of Obesity (EASO) (which organises the European Congress on Obesity), The European Federation of the Associations of Dietitians (EFAD) and the European Collation for Patients with Obesity (ECPO) have come together to produce this new consensus statement that covers a wide range of issues connected with obesity drugs.
These include:
Medical nutritional therapy (MNT): MNT delivered by a registered dietitian is central to obesity care and complements IBTs. The statement highlights the role of dietitians in providing, for example, advice on correct nutrition to ensure protein, vitamin and mineral intake is adequate; and also dose-scaling of obesity drugs to minimise gastrointestinal side effects. Dietitians are also essential in reinforcing healthy dietary patterns and facilitating long-term behaviour change Furthermore, It is important that MNT is provided with respectful, empowering, weight-inclusive communication that recognizes health beyond the scales.
Nutritional psychology: Although IBTs are generally linked to improved mental health, many people living with obesity have pre-existing psychological vulnerabilities. During the profound identity changes that can accompany significant weight loss there is potential for the re‑emergence of mental health issues. Those trained in mental health within the multidisciplinary care team should be vigilant for these problems and also screen for them before the patient begins using obesity medications. Alcohol use disorders should also be screened for before starting GLP-1 treatment.
Monitoring body composition and functional capacity: analysis of existing trials show 24-30% of weight loss with IBTs is 'fat free mass' (mostly muscle) – but the health implications of this are not yet clear, especially in older adults who have proportionally less muscle mass to begin with.
A pragmatic target, where body-composition data are available, may be to aim for an approximate 3:1 ratio of fat loss to lean-mass loss (i.e., for every 4 kg lost, ≥3 kg fat and ≤1 kg fat-free mass); To monitor body composition and functional status, the consensus statement recommends, consistent with the EASO diagnostic framework, to consider moving beyond BMI alone by incorporating central adiposity (waist circumference or waist-to-height ratio) and a pragmatic measure of muscle function (e.g., adjusted handgrip strength or 5x sit-to-stand) with DXA (dual‑energy X‑ray absorptiometry) or BIA (bioelectrical impedance analysis) used where available locally, where costs allow, and particularly for individuals at higher risk of sarcopenia.
Physical Activity (PA) and Exercise In Obesity Management: patients should be helped to understand any physical activity will both help with weight loss and prevent weight gain; as well as helping general and mental health. The consensus statement stresses the importance of muscle-strengthening (resistance) training to help reduce lean body mass loss during obesity management alongside aerobic exercise.
Socioeconomic considerations: Obesity disproportionately affects minority ethnic groups and lower socioeconomic populations, who also have reduced access to specialist services (UK) and IBTs (North America). Socioeconomic deprivation and reliance on public insurance are associated with poorer adherence, while private-pay models further exacerbate affordability barriers.
Provision of IBTs is also influenced by regional regulations and prescribing guidance; people with obesity without diagnosed complications are often disadvantaged compared with those with diagnosed obesity-related complications – in other words, there continues to be a stigma surrounding treating obesity itself as a disease especially it does not have comorbid complications. The consensus statement says that policy should expand IBT coverage and address stigma, while clinical services should improve access to dietitian-led MNT, which could reduce inequalities, improve adherence and outcomes.
The consensus statement also addresses future research priorities that must be addressed to fill various knowledge and evidence gaps. A systematic review of 417 IBT randomised controlled trials showed that less than 20% reported dietary intake or nutritional biomarkers and less than 5% reported bone, micronutrient or physical-function outcomes, leaving major gaps across nutritional, functional and psychological domains.
The authors say: "Research priorities include a core outcome set for IBT trials ; robust nutritional-safety surveillance (including malnutrition screening tools); evaluation of muscle function and performance , mobility and strength outcomes; strategies to preserve lean mass and bone; optimal protein intake during IBT treatment; psychological outcomes and targeted supports; dose-titration methods that reduce discontinuation due to gastrointestinal side effects; haematological and pharmacokinetic safety; mixed-methods studies of the 'real world' lived-experience; and post-cessation, post-obesity surgery and special-population studies."
They conclude: "IBTs represent a paradigm shift in obesity care; optimal implementation includes dietitian-led medical nutrition therapy with integrated psychological and functional support. Priorities are mitigating gastrointestinal effects, preventing micronutrient deficiencies, and preserving lean mass via adequate protein, fibre, fluids and nutrient-dense foods, alongside resistance training, targeted supplementation and regular monitoring, with attention to identity, coping and disordered-eating. Research is needed, to evaluate long-term nutritional, functional and psychological outcomes, develop obesity-specific malnutrition tools, and test strategies to protect muscle and bone."
