Classification of obesity: significance, controversies, and consensus

WANG Yong, KUANG Li-run

Chinese Journal of Practical Surgery ›› 2026, Vol. 46 ›› Issue (9) : 1190-1193.

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Chinese Journal of Practical Surgery ›› 2026, Vol. 46 ›› Issue (9) : 1190-1193. DOI: 10.19538/j.cjps.issn1005-2208.2026.09.05

Classification of obesity: significance, controversies, and consensus

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Abstract

Obesity is markedly heterogeneous, and no single weight-based measure adequately captures fat distribution, metabolic risk, organ damage, and functional status. Obesity classification can complement body mass index (BMI) -based assessment, identify high-risk populations, define treatment priorities and individualized goals, and support efficacy monitoring and shared decision-making. Controversies remain over whether newer systems should replace traditional BMI-centered frameworks, how to distinguish risk states from clinical disease, whether precision phenotypes can directly guide pharmacotherapy or procedure selection, and whether complex assessments are accessible and equitable. Current consensus supports retaining BMI as a simple screening measure and an anchor for the existing evidence base, while integrating population-specific thresholds, obesity-related disease burden, organ and physical function, and specific etiologies into stratified assessment. Other classification systems should remain complementary and, at present, should not independently determine treatment eligibility or procedure selection. High-risk patients should be prioritized for care rather than excluded from treatment, and should undergo dynamic reassessment before and after treatment. Prospective, outcome-oriented studies should validate the reproducibility, predictive value, and clinical utility of different classification systems.

Key words

obesity classification / body mass index / metabolic phenotype / clinical obesity / metabolic and bariatric surgery

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WANG Yong , KUANG Li-run. Classification of obesity: significance, controversies, and consensus[J]. Chinese Journal of Practical Surgery. 2026, 46(9): 1190-1193 https://doi.org/10.19538/j.cjps.issn1005-2208.2026.09.05

References

[1]
国家卫生健康委员会办公厅. 肥胖症诊疗指南(2024年版)[EB/OL]. (2024-10-17)[2026-08-02]. https://www.nhc.gov.cn/yzygj/c100068/202410/18966b78087d44429f934a2ef028b027.shtml.
[2]
Linge J, Cariou B, Neeland IJ, et al. Skewness in body fat distribution pattern links to specific cardiometabolic disease risk profiles[J]. J Clin Endocrinol Metab, 2024, 109(3):783-791.DOI:10.1210/clinem/dgad570.
[3]
Kang PS, Neeland IJ. Body fat distribution,cardiometabolic risk,and practical tools for implementation[J]. Curr Cardiol Rep, 2023, 25(11):1555-1564.DOI:10.1007/s11886-023-01969-5.
[4]
Mohammadian Khonsari N, Khashayar P, Shahrestanaki E, et al. Normal weight obesity and cardiometabolic risk factors: A systematic review and meta-analysis[J]. Front Endocrinol(Lausanne), 2022, 13:857930.DOI:10.3389/fendo.2022.857930.
[5]
Donini LM, Busetto L, Bischoff SC, et al. Definition and diagnostic criteria for sarcopenic obesity: ESPEN and EASO consensus statement[J]. Clin Nutr, 2022, 41(4):990-1000.DOI:10.1016/j.clnu.2021.11.014.
Loss of skeletal muscle mass and function (sarcopenia) is common in individuals with obesity due to metabolic changes associated with a sedentary lifestyle, adipose tissue derangements, comorbidities (acute and chronic diseases), and during the ageing process. Co-existence of excess adiposity and low muscle mass/function is referred to as sarcopenic obesity (SO), a condition increasingly recognized for its clinical and functional features that negatively influence important patient-centred outcomes. Effective prevention and treatment strategies for SO are urgently needed, but efforts are hampered by the lack of an universally established SO Definition and diagnostic criteria. Resulting inconsistencies in the literature also negatively affect the ability to define prevalence as well as clinical relevance of SO for negative health outcomes.The European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO) launched an initiative to reach expert consensus on a Definition and diagnostic criteria for SO. The jointly appointed international expert panel proposes that SO is defined as the co-existence of excess adiposity and low muscle mass/function. The diagnosis of SO should be considered in at-risk individuals who screen positive for a co-occurring elevated body mass index or waist circumference, and markers of low skeletal muscle mass and function (risk factors, clinical symptoms, or validated questionnaires). Diagnostic procedures should initially include assessment of skeletal muscle function, followed by assessment of body composition where presence of excess adiposity and low skeletal muscle mass or related body compartments confirm the diagnosis of SO. Individuals with SO should be further stratified into Stage I in the absence of clinical complications, or Stage II if cases are associated with complications linked to altered body composition or skeletal muscle dysfunction.ESPEN and EASO, as well as the expert international panel, advocate that the proposed SO Definition and diagnostic criteria be implemented into routine clinical practice. The panel also encourages prospective studies in addition to secondary analysis of existing datasets, to study the predictive value, treatment efficacy, and clinical impact of this SO definition.Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.
[6]
Veronese N, Ragusa FS, Pegreffi F, et al. Sarcopenic obesity and health outcomes: An umbrella review of systematic reviews with meta-analysis of observational studies[J]. J Cachexia Sarcopenia Muscle, 2024, 15(4):1264-1274.DOI:10.1002/jcsm.13502.
Many studies support the idea that sarcopenic obesity (SO) could be considered a potential risk factor for negative health outcomes. These results have been inconsistent, and no umbrella reviews exist regarding this topic. Several databases until November 2023 were searched for systematic reviews with meta-analysis of observational studies (cross-sectional, case-control and prospective). For each association, random-effects summary effect sizes with correspondent 95% confidence intervals (CIs) were evaluated using the GRADE tool. Among the 213 papers initially screened, nine systematic reviews with meta-analysis were included, for a total of 384 710 participants. In cross-sectional and case-control studies, 30 different outcomes were analysed, and 18 were statistically significant. In any population addressed in cross-sectional and case-control studies, compared with non-SO, SO increased the prevalence of cognitive impairment (k = 3; odds ratio [OR] = 3.46; 95% CI: 2.24-5.32; high certainty of evidence), coronary artery disease (k = 2; OR = 2.48; 95% CI: 1.85-3.31) and dyslipidaemia (k = 3; OR = 2.50; 95% CI: 1.51-4.15). When compared with sarcopenia or obesity, the results were conflicting. In prospective studies, the association between SO-compared with non-SO-and other negative outcomes was supported by low/very low certainty of evidence and limited to a few conditions. Besides, no comparison with sarcopenia or obesity was provided. Finally, only a few studies have considered muscle function/physical performance in the diagnostic workup. SO could be considered a risk factor only for a few conditions, with the literature mainly based on cross-sectional and case-control studies. Future studies with clear definitions of SO are needed for quantifying the importance of SO-particularly when compared with the presence of only sarcopenia or obesity-and the weight of muscle function/physical performance in its definition.© 2024 The Author(s). Journal of Cachexia, Sarcopenia and Muscle published by Wiley Periodicals LLC.
[7]
Gómez-Zorita S, Queralt M, Vicente MA, et al. Metabolically healthy obesity and metabolically obese normal weight: A review[J]. J Physiol Biochem, 2021, 77(1):175-189. DOI:10.1007/s13105-020-00781-x.
Despite the general relationship between obesity and its co-morbidities, there are both obese individuals who scarcely present the associated pathologies (metabolically healthy obese; MHO) and individuals who present obesity alterations despite having normal weight (metabolically obese normal weight; MONW). It is still difficult to define metabolically MHO and MONW individuals because different classifications have been used in the studies reported. Indeed, different inclusion criteria have been used to discriminate between metabolically healthy and metabolically unhealthy subjects. Due to this and other reasons, such as differences in ethnicity, genetics, and lifestyle of the populations, data concerning the prevalence of MHO and MONW are very variable. The main determinants of MHO are type of growth (hypertrophy or hyperplasia), anatomical location, inflammation of adipose tissue, ectopic fat accumulation, genetic factors, and lifestyles factors. In the case of MONW, the main determinants are genetic background and lifestyle factors. With regard to treatment, it is not clear whether MHO subjects would benefit from traditional lifestyle interventions, based on diet energy restriction and increased physical activity. For MONW subjects, there is still no specialized treatment, and the therapies are the same as those used in obese subjects.
[8]
Zhang X, Zhu J, Kim JH, et al. Metabolic health and adiposity transitions and risks of type 2 diabetes and cardiovascular diseases: A systematic review and meta-analysis[J]. Diabetol Metab Syndr, 2023, 15(1):60. DOI:10.1186/s13098-023-01025-w.
Metabolic health status and levels of adiposity are prone to change over time. Mixed results have been reported regarding the extent by which changes in metabolic health and weight affect cardiometabolic risks. This systematic review and meta-analysis aims to examine the association between transitions in metabolic health and adiposity status on risk of incident type 2 diabetes (T2DM) and cardiovascular disease (CVD) events.A systematic literature search was conducted on MEDLINE and EMBASE through August 2022 for prospective cohort studies examining transitions in metabolic health and adiposity status and risk of incident T2DM and CVDs without restrictions on language or publication status. Meta-analysis was performed to summarize hazard ratios for T2DM and composite CVD events separately using random-effects model.A total of 17 studies were included. Compared to stable metabolically healthy status, transition to metabolically unhealthy status significantly increased the risk of incident T2DM and composite CVD events among individuals with normal weight and individuals with overweight/obesity. Compared to stable metabolically unhealthy status, transition to metabolically healthy status significantly lowered the risk among individuals with normal weight and individuals with overweight/obesity. When metabolic health status remained unchanged, progression from normal weight to overweight/obesity significantly increased risk of CVDs but not risk of T2DM.The impact of change in metabolic health on the risks of T2DM and CVD is more prominent than that of change to body mass index category. Obesity treatment should consider prioritizing improvement in metabolic health parameters over focusing on the extent of weight loss only.© 2023. The Author(s).
[9]
Mathis BJ, Tanaka K, Hiramatsu Y. Factors of interventions for metabolically healthy obesity: A systematic review[J]. Curr Obes Rep, 2023, 12(1):36-60. DOI:10.1007/s13679-023-00494-4.
[10]
Nadolsky K, Garvey WT, Agarwal M, et al. American Association of Clinical Endocrinology consensus statement: Comprehensive clinical care for persons with obesity-2025 update[J]. Endocr Pract, 2025, 31(11):1351-1394.DOI:10.1016/j.eprac.2025.07.017.
[11]
American Diabetes Association Professional Practice Committee for Obesity. Screening, diagnosis,and treatment of preclinical obesity and clinical obesity in adults: Standards of care in overweight and obesity-2026[J]. BMJ Open Diabetes Res Care, 2026, 13(suppl):e006247. DOI:10.1136/bmjdrc-2026-006247.
[12]
Busebee B, Ghusn W, Cifuentes L, et al. Obesity: A review of pathophysiology and classification[J]. Mayo Clin Proc, 2023, 98(12):1842-1857. DOI:10.1016/j.mayocp.2023.05.026.
Obesity is a chronic, multifactorial, and morbid disease. In the United States, 69% of adults are overweight or have obesity, and the global prevalence of obesity is increasing. Obesity is influenced by genetic, neurologic, metabolic, enteric, and behavioral processes. It remains a key modifiable risk factor for many comorbid diseases, including cardiovascular disease, diabetes mellitus, and cancer. Whereas there are recent and significant advances in obesity therapy, including diets, lifestyle modifications, pharmacotherapies, endoscopic procedures, and bariatric surgeries, there is an immense need for a better understanding of the heterogeneity in the pathophysiologic process of obesity and outcomes. Here we review salient pathophysiologic mechanisms underlying the development and morbidity of obesity as well as pathophysiologically based classification systems that inform current obesity management and may inform improved and individualized management in the future.Copyright © 2023 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.
[13]
Ko TYL, Miras AD, Pournaras DJ, et al. Beyond BMI: Consensus definition and diagnostic criteria for clinical obesity[J]. Clin Obes, 2026, 16(1):e70045.DOI:10.1111/cob.70045.
[14]
Rubino F, Cummings DE, Eckel RH, et al. Definition and diagnostic criteria of clinical obesity[J]. Lancet Diabetes Endocrinol, 2025, 13(3):221-262.DOI:10.1016/S2213-8587(24)00316-4.
[15]
Fitch AK, Malhotra S, Conroy R. Monogenic and syndromic obesity[J]. Obes Pillars, 2024, 11:100110. DOI:10.1016/j.obpill.2024.100110.
[16]
Argente J, Farooqi IS, Chowen JA, et al. Hypothalamic obesity: From basic mechanisms to clinical perspectives[J]. Lancet Diabetes Endocrinol, 2025, 13(1):57-68.DOI:10.1016/S2213-8587(24)00283-3.
[17]
Acosta A, Camilleri M, Abu Dayyeh B, et al. Selection of antiobesity medications based on phenotypes enhances weight loss: A pragmatic trial in an obesity clinic[J]. Obesity(Silver Spring), 2021, 29(4):662-671.DOI:10.1002/oby.23120.
[18]
Patti AM, Giglio RV, Ciaccio M, et al. Obesity phenotypes: A narrative review[J]. Medicina(Kaunas), 2025, 61(4):664.DOI:10.3390/medicina61040664.
[19]
中华医学会外科学分会甲状腺及代谢外科学组, 中国医师协会外科医师分会肥胖和糖尿病外科医师委员会. 中国肥胖及代谢病外科治疗指南(2024版)[J]. 中国实用外科杂志, 2024, 44(8):841-849.DOI:10.19538/j.cjps.issn1005-2208.2024.08.01.
[20]
Salminen P, Kow L, Aminian A, et al. IFSO consensus on definitions and clinical practice guidelines for obesity management-An international Delphi study[J]. Obes Surg, 2024, 34(1):30-42.DOI:10.1007/s11695-023-06913-8.
This survey of international experts in obesity management was conducted to achieve consensus on standardized definitions and to identify areas of consensus and non-consensus in metabolic bariatric surgery (MBS) to assist in an algorithm of clinical practice guidelines for the management of obesity.A three-round Delphi survey with 136 statements was conducted by 43 experts in obesity management comprising 26 bariatric surgeons, 4 endoscopists, 8 endocrinologists, 2 nutritionists, 2 counsellors, an internist, and a pediatrician spanning six continents over a 2-day meeting in Hamburg, Germany. To reduce bias, voting was unanimous, and the statements were neither favorable nor unfavorable to the issue voted or evenly balanced between favorable and unfavorable. Consensus was defined as ≥ 70% inter-voter agreement.Consensus was reached on all 15 essential definitional and reporting statements, including initial suboptimal clinical response, baseline weight, recurrent weight gain, conversion, and revision surgery. Consensus was reached on 95/121 statements on the type of surgical procedures favoring Roux-en-Y gastric bypass, sleeve gastrectomy, and endoscopic sleeve gastroplasty. Moderate consensus was reached for sleeve gastrectomy single-anastomosis duodenoileostomy and none on the role of intra-gastric balloons. Consensus was reached for MBS in patients > 65 and < 18 years old, with a BMI > 50 kg/m, and with various obesity-related complications such as type 2 diabetes, liver, and kidney disease.In this survey of 43 multi-disciplinary experts, consensus was reached on standardized definitions and reporting standards applicable to the whole medical community. An algorithm for treating patients with obesity was explored utilizing a thoughtful multimodal approach.© 2023. The Author(s).
[21]
Eisenberg D, Shikora SA, Aarts E, et al. 2022 American Society for Metabolic and Bariatric Surgery and International Federation for the Surgery of Obesity and Metabolic Disorders: Indications for metabolic and bariatric surgery[J]. Surg Obes Relat Dis, 2022, 18(12):1345-1356. DOI:10.1016/j.soard.2022.08.013.
Major updates to 1991 National Institutes of Health guidelines for bariatric surgery.Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.
[22]
刘洋, 李梦伊, 张鹏, 等. 《肥胖症诊疗指南(2024年版)》减重与代谢手术治疗部分解读[J]. 中国实用外科杂志, 2025, 45(5):533-537.DOI:10.19538/j.cjps.issn1005-2208.2025.05.12.
[23]
Zambon Azevedo V, Bel Lassen P, Aron-Wisnewsky J, et al. The concepts of pre-clinical and clinical obesity[J]. Clin Nutr, 2024, 43(12):254-264.DOI:10.1016/j.clnu.2024.10.037.
[24]
Busetto L, Dicker D, Frühbeck G, et al. A new framework for the diagnosis,staging and management of obesity in adults[J]. Nat Med, 2024, 30(9):2395-2399. DOI:10.1038/s41591-024-03095-3.
[25]
Sweatt K, Garvey WT, Martins C. Strengths and limitations of BMI in the diagnosis of obesity: What is the path forward?[J]. Curr Obes Rep, 2024, 13(3):584-595.DOI:10.1007/s13679-024-00580-1.
This review aims to discuss strengths and limitations of body mass index (BMI) in diagnosing obesity, the use of alternative anthropometric measurements, and potential new technology that may change the future of obesity diagnosis and management.The diagnosis of obesity requires the anthropometric assessment of adiposity. In clinical settings, this should include BMI with confirmation that elevated BMI represents excess adiposity and a measure of fat distribution (i.e., waist circumference (WC), waist to height ratio (WHtR), or WC divided by height (WHR.5R). Digital anthropometry and bioelectric impedance (BIA) can estimate fat distribution and be feasibly employed in the clinic. In addition, the diagnosis should include a clinical component assessing the presence and severity of weight-related complications. As anthropometric measures used in the diagnosis of obesity, BMI is generally sufficient if confirmed to represent excess adiposity, and there are advantages to the use of WHtR over WC to assess fat distribution. BIA and digital anthropometry have the potential to provide accurate measures of fat mass and distribution in clinical settings. There should also be a clinical evaluation for the presence and severity of obesity complications that can be used to stage the disease.© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.

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Funding

Liaoning Provincial Science and Technology Plan Project(2025-BS-0553)
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