Trends in adult body-mass index in 200 countries from 1975 to 2014: A pooled analysis of 1698 population-based measurement studies with 19.2 million participants

Mariachiara Di Cesare, Imperial College London
James Bentham, Imperial College London
Gretchen A. Stevens, Organisation Mondiale de la Santé
Bin Zhou, Imperial College London
Goodarz Danaei, Harvard T.H. Chan School of Public Health
Yuan Lu, Harvard T.H. Chan School of Public Health
Honor Bixby, Imperial College London
Melanie J. Cowan, Organisation Mondiale de la Santé
Leanne M. Riley, Organisation Mondiale de la Santé
Kaveh Hajifathalian, Harvard T.H. Chan School of Public Health
Léa Fortunato, Imperial College London
Cristina Taddei, Università degli Studi di Firenze
James E. Bennett, Imperial College London
Nayu Ikeda, National Institute of Health and Nutrition Tokyo
Young Ho Khang, Seoul National University
Catherine Kyobutungi, African Population & Health Research Center
Avula Laxmaiah, Indian Council of Medical Research
Yanping Li, Harvard T.H. Chan School of Public Health
Hsien Ho Lin, National Taiwan University
J. Jaime Miranda, Universidad Peruana Cayetano Heredia
Aya Mostafa, Ain Shams University
Maria L. Turley, Ministry of Health - New Zealand
Christopher J. Paciorek, University of California, Berkeley
Marc Gunter, Imperial College London
Majid Ezzati, Imperial College London
Ziad A. Abdeen, Al-Quds University
Zargar Abdul Hamid, Center for Diabetes and Endocrine Care
Niveen M. Abu-Rmeileh, Birzeit University
Benjamin Acosta-Cazares, Instituto Mexicano del Seguro Social
Robert Adams, The University of Adelaide
Wichai Aekplakorn, Mahidol University
Carlos A. Aguilar-Salinas, Instituto Nacional de la Nutrición Salvador Zubiran

Copyright © NCD Risk Factor Collaboration


Background Underweight and severe and morbid obesity are associated with highly elevated risks of adverse health outcomes. We estimated trends in mean body-mass index (BMI), which characterises its population distribution, and in the prevalences of a complete set of BMI categories for adults in all countries. Methods We analysed, with use of a consistent protocol, population-based studies that had measured height and weight in adults aged 18 years and older. We applied a Bayesian hierarchical model to these data to estimate trends from 1975 to 2014 in mean BMI and in the prevalences of BMI categories (<18.5 kg/m2[underweight], 18.5 kg/m2to <20 kg/m2, 20 kg/m2to <25 kg/m2, 25 kg/m2to <30 kg/m2, 30 kg/m2to <35 kg/m2, 35 kg/m2to <40 kg/m2, ≥40 kg/m2[morbid obesity]), by sex in 200 countries and territories, organised in 21 regions. We calculated the posterior probability of meeting the target of halting by 2025 the rise in obesity at its 2010 levels, if post-2000 trends continue. Findings We used 1698 population-based data sources, with more than 19.2 million adult participants (9.9 million men and 9.3 million women) in 186 of 200 countries for which estimates were made. Global age-standardised mean BMI increased from 21.7 kg/m2(95% credible interval 21.3-22.1) in 1975 to 24.2 kg/m2(24.0-24.4) in 2014 in men, and from 22.1 kg/m2(21.7-22.5) in 1975 to 24.4 kg/m2(24.2-24.6) in 2014 in women. Regional mean BMIs in 2014 for men ranged from 21.4 kg/m2in central Africa and south Asia to 29.2 kg/m2(28.6-29.8) in Polynesia and Micronesia; for women the range was from 21.8 kg/m2(21.4-22.3) in south Asia to 32.2 kg/m2(31.5-32.8) in Polynesia and Micronesia. Over these four decades, age-standardised global prevalence of underweight decreased from 13.8% (10.5-17.4) to 8.8% (7.4-10.3) in men and from 14.6% (11.6-17.9) to 9.7% (8.3-11.1) in women. South Asia had the highest prevalence of underweight in 2014, 23.4% (17.8-29.2) in men and 24.0% (18.9-29.3) in women. Age-standardised prevalence of obesity increased from 3.2% (2.4-4.1) in 1975 to 10.8% (9.7-12.0) in 2014 in men, and from 6.4% (5.1-7.8) to 14.9% (13.6-16.1) in women. 2.3% (2.0-2.7) of the world's men and 5.0% (4.4-5.6) of women were severely obese (ie, have BMI ≥35 kg/m2). Globally, prevalence of morbid obesity was 0.64% (0.46-0.86) in men and 1.6% (1.3-1.9) in women. Interpretation If post-2000 trends continue, the probability of meeting the global obesity target is virtually zero. Rather, if these trends continue, by 2025, global obesity prevalence will reach 18% in men and surpass 21% in women; severe obesity will surpass 6% in men and 9% in women. Nonetheless, underweight remains prevalent in the world's poorest regions, especially in south Asia.