Limitations of BMI in Characterising Obesity Phenotypes
Nur Azlin Zainal Abidin1✉, Fazliana Mansor1, Liyana Ahmad Zamri1, Farah Huda Mohkiar1, You Zhuan Tan1, Noorizatul Syahira Yusaini1, Nur Iffah Mat Hasan1, Stephanie Frisca Jaini1, Siti Azrinnah Abd Azar1, Siti Mastura Abdul Aziz1, Siti Norfizah Mohd Shaher1, Poh Yue Tsen2, Shu Yu Lim3, Tikfu Gee3
- 1 Nutrition, Metabolism & Cardiovascular Research Centre, Institute for Medical Research, National Institute of Health, Ministry of Health Malaysia.
- 2 Sunway Medical Centre, Bandar Sunway, Petaling Jaya, Selangor.
- 3 IHeal Medical Centre, Menara IGB, Mid Valley City, Kuala Lumpur.
Received 15 October 2026 · Accepted 15 October 2026 · Published 15 October 2026
DOI: https://doi.org/10.5281/zenodo.23394799
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Key messages
- SOP participants have significantly lower body weight and BMI despite obesity.
- Adiposity and glycaemic levels are comparable between SOP and non-SOP groups.
- BMI alone may mask important differences in body composition and metabolic risk.
Abstract
Introduction
BMI classifies obesity but does not account for body composition such as muscle or fat distribution.
Materials and methods
Participants with obesity undergoing metabolic surgery in Klang Valley were studied in a baseline analysis of a multicentre observational cohort. Bioelectrical Impedance Analysis (BIA) was used to measure visceral fat area (VFA), percentage body fat (PBF), and skeletal muscle mass (SMM). Sarcopenic obesity phenotype (SOP) was defined as obesity (BMI ≥ 27.5 kg/m²) plus low SMM (lowest quartile of sex-specific SMM index). Mann–Whitney U test compared continuous variables between SOP and non-SOP groups.
Results
SOP participants had significantly lower body weight and BMI compared to non-SOP participants despite having obesity. There was no significant difference in percentage body fat, visceral fat area, or HbA1c levels between SOP and non-SOP groups, indicating comparable adiposity and glycaemic levels.
Conclusion
Women with SOP have smaller body sizes but equivalent adiposity and glycaemic risks compared to non-SOP women. BMI alone is insufficient as a standalone indicator of obesity. Body composition analysis is essential to accurately identify metabolic risk in these individuals.
Original poster
References
- Wu, Y.; Li, D.; Vermund, S.H. Advantages and Limitations of the Body Mass Index (BMI) to Assess Adult Obesity. Int. J. Environ. Res. Public Health 2024, 21, 757.
- Wu R, Li M, Liao Y, Zhang J, Xu C, Yan X. Prevalence and characteristics of sarcopenic obesity and normal weight obesity in Chinese women: a cross-sectional study based on body fat percentage. BMC Public Health. 2025 Aug 18;25(1):2817.
- Borba VZC, Costa TMDRL. Sarcopenic obesity: a review. Arch Endocrinol Metab. 2025 Apr 11;68:e240084.7173.