The study team, led by Judith E. Guzmán-García of the Pediatric Obesity Clinic at Hospital Regional Materno Infantil and Tecnológico de Monterrey, analyzed 220 patients aged 4 to 16 years who attended the clinic in northeastern Mexico. This was a cross-sectional study, meaning the researchers assessed each child at a single point in time rather than following them over months or years. Every child was classified twice: once using the Centers for Disease Control and Prevention BMI criteria, the standard percentile-based approach familiar to pediatricians worldwide, and once using the Clinical Framework of Obesity 2025, adapted for pediatric use. Under the new framework, children were categorized as having preclinical or clinical obesity depending on whether their excess adiposity was already causing measurable organ-system dysfunction.

The headline result is a substantial gap between the two diagnostic systems. By CDC BMI criteria, 80 percent of the children met the definition of obesity. Under the Clinical Framework of Obesity 2025, that figure rose to 95 percent. The researchers quantified the agreement between the two systems using Cohen’s kappa, a statistical measure that corrects for chance agreement, and found only fair concordance, with a kappa of 0.321 and a p value below 0.001. In practical terms, this means the two frameworks were not simply interchangeable labels for the same phenomenon; they were identifying meaningfully different groups of children as having obesity.

Perhaps the most consequential finding concerns the children that BMI alone would wave through. Clinical obesity, the state in which excess fat is actively damaging organs, was identified in 83.2 percent of the patients under the new framework, and this included children whom the CDC BMI criteria classified as having normal weight or merely overweight. In other words, some children sitting in the supposedly reassuring middle of the BMI chart were already showing signs of obesity-related organ dysfunction. For clinicians who rely on BMI as a screening gatekeeper, that is a sobering result, because those children might never be referred for the metabolic workups that could catch problems early.

Which organ systems were suffering? The metabolic system topped the list, affected in 73.2 percent of the children classified with clinical obesity, followed by the cardiovascular system at 59 percent. These are not trivial findings. Metabolic abnormalities in childhood, such as insulin resistance and dyslipidemia, are well-documented precursors of type 2 diabetes and cardiovascular disease in adulthood, and longitudinal research has shown that risk factors like elevated blood pressure and adverse lipid profiles tend to track from childhood into adult life. The study’s authors note that the framework’s ability to surface this multisystem involvement, even among children with BMI values in the normal or overweight range, is precisely what makes it a potentially valuable complement to conventional anthropometric screening.

The Clinical Framework of Obesity 2025 emerged from a Lancet Commission that sought to redefine obesity not as a body-size category but as a medical condition, one that can exist without illness or can cause overt organ dysfunction. The commission distinguished between preclinical obesity, where excess adiposity is present but organs are still functioning normally, and clinical obesity, where the fat mass itself is driving disease. This conceptual shift matters because it moves the diagnostic question away from how heavy a child is relative to peers and toward what the excess fat is actually doing to the body. In adults, the new definition has already been tested in large cohorts in the United States and Peru, with studies reporting that it reclassifies substantial numbers of people. The Mexican study is among the first to apply the framework, with pediatric adaptations, to a clinical population of children.

Mexico provides a particularly urgent setting for this kind of research. National survey data published in Salud Pública de México show high rates of overweight and obesity among Mexican schoolchildren and adolescents, and global forecasting studies project that childhood obesity will continue to climb worldwide through mid-century. Children with obesity face elevated risks of comorbidities ranging from fatty liver disease, which has been linked to serious liver outcomes in adolescence and young adulthood, to psychosocial difficulties and limitations in daily physical activities. Against that backdrop, a diagnostic tool that better identifies which children are already experiencing organ damage could help clinics triage limited resources toward those at greatest immediate risk.

The authors are careful about the limits of their work, and readers should be too. The Clinical Framework of Obesity 2025 has not yet been validated in pediatric populations, and this study offers preliminary evidence rather than a definitive endorsement. The sample came from a single referral clinic in northeastern Mexico, meaning the children were already selected for concern about weight or metabolic health, so the prevalence figures cannot be generalized to the broader population of Mexican children. The cross-sectional design captures a snapshot rather than a trajectory, so the study cannot say whether children classified as having preclinical obesity would go on to develop clinical disease. The requirement for individual informed consent was waived by the hospital’s ethics committee and the Nuevo León Ministry of Health because the study was retrospective and used de-identified data, and the authors report no competing interests and no external funding.

There is also a live scientific debate about the new definition itself. Commentators in JAMA Network Open and JAMA Pediatrics have questioned whether the new criteria define too many people as obese, with some arguing that expanding the diagnostic umbrella risks pathologizing body sizes without clear evidence of harm, while others counter that the framework finally acknowledges that BMI is an imperfect proxy for adiposity and its consequences. Studies of BMI’s diagnostic performance have long shown that it can miss children with excess fat mass and elevated cardiometabolic risk, and systematic reviews comparing bioelectrical impedance with dual X-ray absorptiometry in pediatric populations highlight how difficult it remains to measure adiposity accurately in children. The Mexican study sits squarely in this contested territory, and its fair kappa value is less a verdict on either system than a demonstration that they are measuring different things.

The practical takeaway from the study is not that BMI should be abandoned, but that it may be insufficient on its own. The authors conclude that applying the Clinical Framework of Obesity 2025 alongside BMI identified additional multisystem involvement that BMI-based classification alone would have overlooked, and they suggest that integrating the two may support a more structured and comprehensive assessment of obesity-related organ involvement in children. For a field in which childhood obesity is increasingly framed as a chronic disease demanding specific health care, that reframing could change how pediatric clinics evaluate their patients: not just how heavy they are, but whether their hearts, livers, and metabolisms are already paying the price. Validation studies in larger and more diverse pediatric populations will be needed before the framework becomes standard practice, but this preliminary evidence from Monterrey suggests that the era of diagnosing childhood obesity with a single calculated number may be drawing to a close.

Subject of Research: Comparison of CDC BMI criteria and the Clinical Framework of Obesity 2025 for diagnosing obesity and organ-system involvement in Mexican children

Article Title: Comparing two diagnostic frameworks for obesity in Mexican children attending a pediatric obesity clinic

Article References: Guzmán-García, J. E., Gomez-Orozco, P., Velasco-Rodríguez, V. M., Martínez-Tapia, M. E., & Rodríguez-Gutiérrez, N. A. (2026). Comparing two diagnostic frameworks for obesity in Mexican children attending a pediatric obesity clinic. Pediatric Research. https://doi.org/10.1038/s41390-026-05479-2

Image Credits: AI Generated

DOI: 10.1038/s41390-026-05479-2

Keywords: pediatric obesity, body mass index, Clinical Framework of Obesity 2025, CDC BMI criteria, clinical obesity, preclinical obesity, metabolic dysfunction, cardiovascular risk, Mexican children, organ-system involvement, diagnostic criteria, Pediatric Research

The Lancet Diabetes and Endocrinology Commission, in its 2025 report, proposed a fundamental reframing of obesity. Rather than treating a high BMI as a diagnosis in itself, the Commission distinguished between clinical obesity, in which excess body fat is accompanied by measurable organ dysfunction or limitations in daily activities, and preclinical obesity, in which excess fat has not yet caused observable harm. The distinction matters because BMI is an imperfect proxy: it overestimates adiposity in muscular individuals and underestimates it in people with central fat accumulation but normal weight. By requiring evidence of organ dysfunction, the new framework aims to identify people whose excess fat is actively damaging their health.

Applying this framework at population scale required an unprecedented collaborative effort. No single cohort had collected all the anthropometric measures, body composition data, and clinical and laboratory markers the Commission’s criteria demand. So the research consortium, known as ECOS, integrated cross-sectional data from 11 population-based cohorts in Australia, Canada, Estonia, Finland, the Netherlands, the United Kingdom, and the United States, covering 44 assessment waves collected between 1996 and 2023. In total, 786,557 participants aged four and above were classified, making this the largest clinical obesity prevalence study conducted to date.

The results reveal a striking age-dependent divergence between BMI-defined and clinical obesity. In early childhood, clinical obesity affected just 3.7 percent of children aged four to five, well below the 8.8 percent prevalence of BMI-defined obesity in the same group. Throughout childhood, adolescence, and early and mid-adulthood, BMI-defined obesity consistently overestimated the burden of clinically significant disease. At ages 35 to 44, for example, 26.3 percent of participants met BMI criteria for obesity, but only 15.1 percent met the Commission’s criteria for clinical obesity. Then the pattern inverts: from age 55 onward, clinical obesity becomes more common than BMI-defined obesity, climbing to 52.0 percent among adults aged 65 to 74.

The organ dysfunction criteria driving these classifications varied systematically with age. Among children with clinical obesity, elevated systolic blood pressure was overwhelmingly the most common finding, present in 87.3 percent of affected four- to nine-year-olds. Renal dysfunction, detected through microalbuminuria, was also most prevalent in childhood, affecting 44.2 percent of young children with clinical obesity. In early and mid-adulthood, liver dysfunction took center stage, with elevated alanine aminotransferase found in 56.3 percent of affected adults aged 20 to 34 and elevated gamma-glutamyl transferase in 48.8 percent of those aged 35 to 54. In later life, musculoskeletal dysfunction dominated, affecting 55.1 percent of people aged 75 and older with clinical obesity.

Sex emerged as a powerful modifier of these patterns. From adolescence through mid-adulthood, males carried a higher prevalence of clinical obesity than females; at ages 35 to 44, 18.6 percent of men versus 13.9 percent of women met the criteria. But from age 55 onward the relationship reversed, with women showing markedly higher prevalence. At ages 65 to 74, 57.1 percent of women had clinical obesity compared with 44.1 percent of men, and female prevalence peaked at 58.5 percent at ages 75 to 84. Preclinical obesity followed a different trajectory: in women it rose through early adulthood, peaked in the mid-thirties to mid-forties, and then declined, whereas in men it remained relatively constant across the life course. The authors suggest these divergences may partly reflect survival bias and differences in how excess adiposity manifests between the sexes, though the underlying biology remains to be fully explored.

Socioeconomic position, measured through education level, showed a more modest influence. Across all age groups, clinical obesity prevalence was slightly lower among people with high education compared with those in the middle and low education categories; at ages 65 to 74, prevalence was 46.8 percent in the high education group versus 53.9 and 55.0 percent in the middle and low groups respectively. The age-dependent patterns of both clinical and preclinical obesity were broadly similar across all three education strata, suggesting that while education shapes obesity risk, the relationship between excess fat and organ dysfunction follows a comparable life course architecture regardless of socioeconomic background.

The study also exposed how sensitive prevalence estimates are to the specific measures chosen to define excess adiposity. In a subgroup of cohorts with complete anthropometric and body composition data, waist-to-height ratio was met by virtually all participants classified with clinical or preclinical obesity, between 95.4 and 100 percent depending on the cohort, while body fat percentage was the least commonly satisfied criterion, met by as few as 9.6 percent of UK Biobank participants with clinical obesity. When excess adiposity was defined by any two anthropometric criteria, clinical obesity prevalence in adults ranged from 5.2 percent at ages 20 to 24 to 51.2 percent at ages 65 to 74, substantially higher than estimates based on BMI plus one anthropometric measure or body fat percentage alone. These differences carry real consequences for diagnosis, risk prediction, and treatment eligibility.

The authors are candid about the limitations inherent in retrofitting a new diagnostic framework onto data collected before it existed. No cohort captured all 13 diagnostic domains specified by the Commission, meaning clinical obesity prevalence was likely underestimated in some groups. Data on central nervous system, respiratory, lymphatic, and reproductive criteria were sparse or absent, and the researchers could not always verify that observed organ dysfunction was genuinely attributable to excess adiposity rather than to other common conditions of later life. Laboratory thresholds varied across jurisdictions, and the treatment of medicated conditions, such as hypertension controlled by antihypertensive drugs, required pragmatic decisions that the Commission’s guidelines do not address. The cohorts were also predominantly from high-income, majority-White populations, limiting generalizability to more diverse settings where the burden of obesity is growing fastest.

Despite these caveats, the consistency of the life course pattern across cohorts from different countries, recruitment epochs, and measurement protocols lends weight to the central conclusion: clinical obesity is rarer than BMI-defined obesity in childhood and early adulthood, but substantially more common in later life. The findings underscore an urgent need for prospective longitudinal studies with standardized collection of all diagnostic criteria, which would allow researchers to track how individuals transition from preclinical to clinical obesity and to determine whether early identification and intervention in childhood, a critical window for prevention, can alter that trajectory. For now, the study provides the most comprehensive picture yet of what the new definition of obesity means for real populations, and it suggests that the number on the scale, and even the ratio of weight to height, may be far less informative than the quiet damage that excess fat does to organs over decades of exposure.

Subject of Research: Life course prevalence of clinical and preclinical obesity using the Lancet Commission diagnostic criteria

Article Title: The lancet commission definition of clinical obesity: a multi-cohort cross-sectional analysis from early childhood to older age in seven high-income countries

Article References: Longmore, D. K., MacKechnie, G. P., Huntington, P. A., Chen, Z. H., de Groot, J., Mikkonen, S., Mykkänen, J., Pätsi, S., Puusepp, T., Fischer, K., Jaddoe, V., Kerr, J. A., Lakka, T. A., Lehtimäki, T., Miliku, K., Nedelec, R., Ponsonby, A.-L., Sebert, S., Vuillermin, P., … Viikari, J. (2026). The lancet commission definition of clinical obesity: a multi-cohort cross-sectional analysis from early childhood to older age in seven high-income countries. eClinicalMedicine, Article 104231. https://doi.org/10.1016/j.eclinm.2026.104231

Image Credits: AI Generated

DOI: 10.1016/j.eclinm.2026.104231

Keywords: clinical obesity, preclinical obesity, Lancet Commission, body mass index, organ dysfunction, life course epidemiology, adiposity, pediatric obesity, cohort study, prevalence, metabolic health, public health

The authors ground their argument in a conceptual shift that has been gathering force since the Lancet Commission on the Definition of Clinical Obesity published its diagnostic framework in 2025. That commission drew a sharp line between preclinical obesity, a state of elevated risk in which organs still function normally, and clinical obesity, an established disease in which excess adiposity has begun to damage organs or limit physical function. This is not semantic hair-splitting. The distinction determines who needs what, and when. A patient with preclinical obesity may be well served by lifestyle support and, in some cases, medication to prevent progression. A patient with clinical obesity, whose joints, liver, heart, or metabolism are already failing under the burden of diseased fat tissue, may need interventions powerful enough to reverse established organ dysfunction, and quickly.

Cohen and his colleagues contend that failing to make this distinction carries four concrete harms. First, clinicians may delay escalating treatment for patients with clinical disease, the very group that benefits most from definitive therapy, while they wait to see whether a drug trial will succeed. Second, patients at the preclinical stage risk over-medicalization, receiving intensive and costly interventions they do not yet require. Third, when clinical trials enroll undifferentiated populations that mix these two states, the measured treatment effects become diluted, obscuring which therapy truly helps whom. Fourth, health systems with finite resources end up spending them inefficiently, funding interventions for people who would have done well with less while rationing them from people whose disease demands more. The positioning of surgery, in other words, is not an organizational detail but a question with direct clinical and economic stakes.

So what does the evidence say surgery can still deliver? The authors describe metabolic bariatric surgery as remaining among the most durable interventions available for clinical obesity. Operations such as sleeve gastrectomy and gastric bypass do more than restrict intake; they alter gut hormone signaling, appetite regulation, and glucose metabolism in ways that reduce adiposity, improve organ function, and, in a substantial fraction of patients, drive remission of obesity-related conditions including type 2 diabetes. Where a daily injectable drug works only for as long as it is taken, a surgical intervention produces anatomical and hormonal changes that persist. Long-term observational cohorts and randomized trials have documented weight loss and cardiometabolic benefit extending well beyond a decade after operation, a horizon no current pharmacotherapy has matched in head-to-head comparison.

The safety picture has also changed almost beyond recognition. The perspective emphasizes that over the past three decades surgical practice has evolved through technical refinement, standardized protocols, and systematic perioperative optimization. Contemporary bariatric surgery, supported by randomized clinical trials and mature long-term observational datasets, is described by the authors as a very safe therapeutic option for patients with advanced obesity and complex metabolic disease. Mortality rates for modern procedures are comparable to those of routine general surgery such as gallbladder removal, a statistic that surprises many clinicians whose mental image of the field was formed in an earlier era. The operations themselves have been refined laparoscopically and, increasingly, robotically, with shorter hospital stays and fewer complications than the open procedures of the 1990s.

Yet the authors do not dismiss the new pharmacotherapy; quite the opposite. Their argument is that glucagon-like peptide-1 receptor agonists and related agents are legitimate, powerful tools that belong inside a multimodal treatment framework, not rivals to be defeated. The framework they envision integrates behavioral, pharmacological, endoscopic, and surgical interventions, matched to disease stage and adapted over time. A patient might begin with structured lifestyle change and medication, add an endoscopic or pharmacological escalation if response is inadequate, and proceed to surgery when clinical obesity is established or when pharmacotherapy fails, is not tolerated, or is discontinued. Surgery, in this model, is not the option of last resort after everything else has failed, nor the reflexive first move. It is one instrument in a staged repertoire, deployed according to disease severity and patient goals.

The real-world behavior of patients on the new drugs adds urgency to this reasoning. A 2025 analysis in JAMA Network Open tracked discontinuation and reinitiation of dual-labeled GLP-1 receptor agonists among United States adults with overweight or obesity and documented substantial rates of patients stopping their medication, a pattern consistent with the well-known challenges of cost, supply, side effects, and waning motivation that accompany chronic injectable therapy. Weight regain after discontinuation is a predictable consequence of stopping an appetite-suppressing drug, because the underlying biology of obesity has not changed. The authors point to this fragility of pharmacological maintenance as precisely the scenario in which a durable intervention such as surgery retains its value, either as primary therapy for selected patients or as a rescue strategy after pharmacotherapy-induced weight loss plateaus or reverses. The International Federation for the Surgery of Obesity has already issued a formal statement, co-authored by several of the same authors, addressing how to position surgery after drug-induced weight loss in patients with clinical obesity.

Economics complicates the picture further. Two recent analyses cited in the perspective tackle the cost question directly. A matched cohort study published in Surgery for Obesity and Related Diseases in 2025 examined the cost-effectiveness of bariatric surgery and found grounds for arguing that surgical treatment pays for itself over time through reduced management of diabetes, cardiovascular disease, and other obesity complications. A separate cost comparison in Surgical Endoscopy asked where the break-even point lies between GLP-1 receptor agonists and surgery, a question that becomes pointed when a medication must be taken indefinitely at an annual cost that can exceed the one-time price of an operation within a few years. Health systems cannot fund everything for everyone, and the authors argue that stage-adapted care, in which expensive definitive therapy is reserved for established clinical disease, is the most defensible way to allocate limited resources while still offering earlier, less intensive support to those at risk.

Digital therapeutics form the final piece of the multimodal puzzle. A randomized controlled trial published in the same journal in 2026 evaluated a digital health application for weight management in people with obesity and reported six-month efficacy results, illustrating how digitally enabled care pathways are being woven into the therapeutic landscape alongside drugs and surgery. The authors view these tools not as competitors but as connective tissue: platforms that can extend behavioral support, monitor patients after surgery, flag weight regain, and coordinate escalation between treatment modalities. In an integrated system, a patient’s care might move fluidly between an app, a prescribing physician, an endoscopist, and a surgeon, with each step justified by measured disease status rather than by the habits or incentives of any single specialty.

The perspective’s ultimate message is a call for clinical discipline in a moment of therapeutic enthusiasm. Effective drugs have not made surgery obsolete, and surgery has not made drugs unnecessary; instead, the new diagnostic framework of clinical obesity gives clinicians a principled way to decide which patient needs which tool, and when. Mispositioning surgery, the authors warn, will delay definitive treatment for the sickest patients, while abandoning pharmacotherapy would deny many others a safer, less invasive path. The task for the coming decade is to build care pathways that treat obesity as the heterogeneous, chronic, progressive disease it is, matching the durability of the scalpel and the flexibility of the syringe to the stage of the disease in front of the clinician. In that matching, the authors conclude, lies the future of obesity medicine.

Subject of Research: Positioning of metabolic bariatric surgery within multimodal obesity care in the era of effective pharmacotherapy

Article Title: Where does surgery fit in the era of effective obesity pharmacotherapy? Positioning metabolic bariatric surgery within multimodal obesity care

Article References: Cohen, R. V., Salminen, P., Ponce, J., & Prager, G. (2026). Where does surgery fit in the era of effective obesity pharmacotherapy? Positioning metabolic bariatric surgery within multimodal obesity care. International Journal of Obesity. https://doi.org/10.1038/s41366-026-02215-y

Image Credits: AI Generated

DOI: 10.1038/s41366-026-02215-y

Keywords: obesity, bariatric surgery, metabolic surgery, GLP-1 receptor agonists, pharmacotherapy, clinical obesity, Lancet Commission, multimodal treatment, digital health, cost-effectiveness, weight regain, International Journal of Obesity

The study, led by Saurav Basu of ESI-PGIMSR and ESIC Medical College in Kolkata together with Shubhanjali Roy of the Indian Institute of Public Health-Delhi, drew on Wave 1 of the Longitudinal Ageing Study in India, or LASI, a nationally representative survey coordinated by the International Institute for Population Sciences in Mumbai. The researchers analyzed data from 60,640 adults aged 45 years or older, classifying each participant into one of three categories: no obesity, preclinical obesity, or clinical obesity. The classification operationalized the 2025 Lancet consensus definition of clinical obesity at a population scale for the first time, distinguishing people who carry excess adiposity but have not yet developed obesity-related illness from those whose excess fat is already manifesting as diagnosed disease.

Technically, the framework moved beyond the conventional reliance on body mass index alone. The researchers integrated Asian-specific BMI thresholds, which recognize that harmful levels of body fat occur at lower BMI values in South Asian populations than in European ones, with Asian-specific waist circumference cut-offs that capture central or abdominal adiposity, the pattern of fat deposition most strongly linked to metabolic risk. These anthropometric measures were then combined with self-reported physician-diagnosed conditions, including hypertension, diabetes, chronic heart disease, chronic bone or joint disease, and high cholesterol, to determine whether an individual’s excess adiposity had crossed the threshold into clinical obesity.

The headline numbers are striking. Overall, 37.53 percent of older Indian adults had either preclinical or clinical obesity. Of these, 15.00 percent fell into the preclinical category, carrying excess adiposity without a diagnosed obesity-related condition, with a 95 percent confidence interval of 14.27 to 15.75 percent. The remaining 22.53 percent had clinical obesity, meaning their excess body fat was accompanied by one or more physician-diagnosed comorbidities, with a confidence interval of 21.71 to 23.37 percent. The remaining 62.47 percent of participants, with a confidence interval of 61.55 to 63.39 percent, were classified as not having obesity. In other words, for every two older Indians with obesity-related disease already diagnosed, roughly one more carries excess fat that has not yet translated into illness, a hidden reservoir of future risk.

Perhaps more revealing than the prevalence figures are the determinants that emerged from the study’s multivariable regression models, which adjusted for a wide range of sociodemographic, behavioral, and psychosocial factors. Women had nearly double the odds of moving up the obesity severity spectrum compared with men, with an adjusted odds ratio of 1.97. Urban residents had 88 percent higher odds than their rural counterparts, with an adjusted odds ratio of 1.88, a finding consistent with the well-documented role of urban environments in promoting sedentary lifestyles, altered diets, and cardiometabolic risk. Individuals in the richest quintile of household monthly per capita expenditure had 91 percent higher odds than those in the poorest, an adjusted odds ratio of 1.91, underscoring that in India the obesity epidemic currently tracks socioeconomic advantage rather than deprivation.

One of the most intriguing findings concerns the social dimension of obesity. Individuals classified as socially isolated, measured using validated social network assessment tools, had 44 percent higher odds of belonging to a higher obesity category, with an adjusted odds ratio of 1.44. This aligns with a growing international literature linking loneliness and weak social ties to weight gain, poorer health behaviors, and worse chronic disease outcomes. Whether social isolation drives obesity through reduced physical activity, altered eating patterns, chronic stress, or some combination of these pathways remains an open question, but the association persisted even after adjustment for depression scores measured with the CES-D scale and other confounders. The finding suggests that obesity interventions in ageing populations may need to consider social connection as seriously as diet and exercise.

Age itself told a more complex story. Adults aged 70 and above had lower odds of being in a higher obesity category compared with younger participants, with an adjusted odds ratio of 0.80. This pattern may partly reflect survivor effects, as individuals with the most severe obesity-related disease may not survive into the oldest age groups, as well as natural changes in body composition with advancing age. It also reflects the known limitations of BMI in very old adults, where sarcopenia, the age-related loss of muscle mass, can mask adiposity behind a deceptively normal weight. The phenotype-based approach used in this study, which incorporates waist circumference rather than relying on BMI alone, is designed to be more sensitive to these age-related shifts in body composition.

The morbidity burden associated with the obesity phenotypes was substantial. Compared with participants without obesity, those with preclinical or clinical obesity had higher prevalence of hypertension, diabetes, chronic heart disease, chronic bone or joint disease, high cholesterol, and multimorbidity, the co-occurrence of two or more chronic conditions. The gradient across phenotypes is clinically meaningful: preclinical obesity identifies people with excess adiposity who have not yet accumulated diagnosed disease, while clinical obesity identifies those in whom the disease process has already declared itself. This distinction, the authors argue, adds diagnostic value beyond BMI by enabling refined risk stratification at the population level, allowing health systems to target intensive management toward those with established disease while directing early identification and prevention toward those at the preclinical stage.

The biological rationale for this phenotyping is well established. Excess adipose tissue, particularly visceral fat, is not a passive energy store but an active endocrine and inflammatory organ. Chronic low-grade inflammation originating in adipose tissue is a recognized mechanism linking obesity to insulin resistance, type 2 diabetes, fatty liver disease, and cardiovascular disease. In older adults, the interaction between obesity and declining muscle strength further accelerates mobility loss and functional impairment. By distinguishing between adiposity that has and has not yet produced clinical manifestations, the new framework attempts to resolve long-standing debates over the heterogeneous health significance of elevated BMI, including the contested concept of metabolically healthy obesity.

For India, the stakes are considerable. The country is undergoing a well-documented nutrition transition, with rising consumption of ultra-processed foods, declining physical activity, and expanding urbanization driving an epidemic of noncommunicable diseases. Routine obesity diagnosis in Indian clinical practice and national surveys has traditionally leaned heavily on BMI, which fails to capture the metabolic heterogeneity that this study reveals. The authors argue that public health strategies should strengthen early identification of high-risk individuals, integrate waist circumference measurement and morbidity assessment into existing noncommunicable disease screening programs for older adults, and address the social and structural factors, from urban design to social isolation, that shape the obesity burden.

The study’s scale and representativeness lend its conclusions unusual weight, though the authors note that it is based on a secondary analysis of de-identified, publicly available LASI Wave 1 data, with diagnoses relying on self-reported physician diagnoses rather than direct clinical examination. Even with those limitations, the message is clear: obesity in ageing India is common, socially patterned, and already deeply entangled with chronic disease, and recognizing the difference between carrying excess fat and being made sick by it could transform how the country, and other nations facing similar transitions, approach the epidemic. As populations worldwide grow older and heavier, the Indian findings offer both a warning about the scale of hidden preclinical risk and a practical template for identifying, stratifying, and ultimately reducing the morbidity that excess adiposity imposes on ageing societies.

Subject of Research: Prevalence, determinants, and morbidity burden of clinical and preclinical obesity phenotypes among older adults in India

Article Title: Clinical obesity phenotypes among older adults: prevalence, determinants, and morbidity burden from the Longitudinal Ageing Study in India

Article References: Basu, S., & Roy, S. (2026). Clinical obesity phenotypes among older adults: prevalence, determinants, and morbidity burden from the Longitudinal Ageing Study in India. International Journal of Obesity. https://doi.org/10.1038/s41366-026-02226-9

Image Credits: AI Generated

DOI: 10.1038/s41366-026-02226-9

Keywords: obesity, older adults, India, LASI, clinical obesity, preclinical obesity, BMI, waist circumference, multimorbidity, social isolation, noncommunicable diseases, public health