Obesity is more than a number: a framework for treatment

For decades, obesity has been misunderstood and reduced to BMI thresholds that overlook the complexity of the disease. This outdated approach has hindered effective treatment and reinforced stigma. To address this, a shift to recognition of obesity as a systemic disease has been endorsed by over 75 medical societies, including the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO). This new framework emphasizes the physiological impact of excess adipose tissue over weight alone by assessing BMI and one anthropometric measure (for example waist circumference, waist-to-hip or waist-to-height ratio). Of course, a BMI over 40 kg/m² remains a practical threshold for assuming excessive body fat¹.

Unlike traditional models, this new framework differentiates between preclinical obesity—where excess adiposity is present but health is still preserved—and clinical obesity, where adiposity has begun to cause measurable organ dysfunction and illness. This distinction is critical, allowing for early intervention in individuals who are at risk while ensuring that those experiencing the health consequences of obesity receive appropriate evidence-based treatment. Preclinical obesity presents a window of opportunity for preventive intervention, where lifestyle modifications, medical monitoring, and pharmacotherapy or even metabolic bariatric surgery (MBS) can help delay or prevent progression to clinical obesity. The options are chosen according to the person’s risk¹. This approach mirrors other chronic disease models, such as hypertension and diabetes, where early treatment significantly reduces long-term complications. For individuals with clinical obesity, the goal is not just weight loss but comprehensive treatment that addresses organ dysfunction and systemic complications.

The recognition of obesity as a disease rather than a lifestyle issue is essential in overcoming the barriers that have long restricted access to treatment. Despite the well-documented impact of obesity on metabolic, cardiovascular, musculoskeletal, and mental health, only 1–2% of eligible individuals receive any medical intervention. MBS is the most effective treatment for severe obesity, resulting in substantial sustained weight reduction with improvement in co-morbidities, quality of life, and increased life expectancy² and still less than 1% of those who could benefit from MBS actually undergo MBS³. This massive gap between treatment eligibility and access stems from stigma^4,5, outdated insurance policies, and a lack of specialized obesity care providers. In many healthcare systems, obesity treatment is only reimbursed if a patient has co-morbidities, which contradicts the growing body of evidence supporting early intervention before organ damage occurs¹—obesity must be treated before it causes irreversible damage.

The future of obesity treatment lies in a multimodal, patient-centred approach, integrating surgical and pharmacological therapies to improve outcomes⁶. Obesity management medications (OMMs)—including next-generation GLP-1 receptor agonists and dual incretin therapies—are transforming care. These medications not only support weight loss but also improve health and reduce cardiovascular risks. The IFSO Consensus on OMMs⁷, recently published in BJS, underscores the importance of pharmacological therapy as both an alternative and an adjunct to surgery, particularly for perioperative management. The integration of MBS and OMMs provides a powerful approach to enhancing treatment efficacy, improving long-term outcomes, and expanding access to care for patients who may not be candidates for surgery or need additional support following surgery⁸. However, ensuring broad access to both these effective treatments remains a challenge. The cost of OMMs is a significant barrier, with many healthcare systems failing to cover these highly effective medications despite their documented benefits⁹. With the current costs of OMMs, MBS is projected to be more cost-effective in patients with severe obesity and type 2 diabetes compared with pharmacotherapy¹⁰.

Long-term patient adherence is a major challenge in obesity care. As a chronic disease, clinical obesity requires lifelong continuous care—not short-term solutions. Obesity has historically been framed as an issue of personal responsibility, yet research consistently shows that biology, genetics, environment, and metabolic dysfunction play key roles. Recognizing this complex aetiology is vital to shifting public perception and delivering compassionate, evidence-based care, recognizing clinical obesity as a standalone disease—not a personal failing.

This evolving understanding presents a powerful opportunity to transform care for millions worldwide. By acknowledging obesity as a chronic disease, expanding access to all proven treatments, and embracing a patient-centred, multimodal approach, we can reduce the global burden of obesity. The real challenge now is translating this new framework into action—through collaboration, policy change, and innovation—so that obesity is treated with dignity and scientific rigour.

Funding

No source of funding.

Disclosures

R.V.C. received research grants from Johnson&Johnson Medtech and Medtronic. Speaker fee from Johnson&Johnson Medtech, Medtronic and NovoNordisk. G.P. received educational grants from NovoNordisk, Johnson&Johson Medtech, Olympus and Medtronic. Speaker fees from Medtronic, Meril and Olympus and scientific advisory bord for Lilly and NovoNordisk. P.S. received lecture fees from Novo Nordisk, grants from Academy of Finland, European Research Council, and Sigrid Juselius Foundation.

Data availability

None.

References