EPIDEMIOLOGY AND HEALTH DATA INSIGHTS
Original Article
Jul 13, 2026 5 4

Socioeconomic Inequalities in Obesity Among Korean Adults: The Role of Lifestyle Factors in KNHANES 2022–2024

Zhansulu Issayeva 1 * ,
Ki-Soo Eun 2
1 Graduate School of International Studies, Seoul National University, Seoul, Republic of Korea 2 Center for Transnational Migration and Social Inclusion (CTMS), Graduate School of International Studies, Seoul National University, Seoul, Republic of Korea* Corresponding Author
Epidemiology and Health Data Insights, 2(5), 2026, ehdi050, https://doi.org/10.63946/ehdi/18958
Publication date: Jul 13, 2026
Full Text (PDF)

ABSTRACT

Background: Obesity is increasingly understood as a health outcome shaped by social conditions, yet evidence on socioeconomic inequalities in obesity in South Korea remains mixed, particularly with regard to lifestyle behaviours and sex differences.
Methods: This study uses pooled data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2022–2024 (N=11,714 adults aged 19–64 years). Obesity was defined as body mass index ≥25 kg/m². Socioeconomic status (SES) was assessed using education, income, occupation, and a composite SES index. Lifestyle factors, including physical activity, smoking, alcohol consumption, sleep duration, and working hours, were included in sequential regression models to assess whether associations between socioeconomic status and obesity were attenuated after adjustment for these factors. Survey-weighted logistic regression models were estimated, with additional analyses stratified by sex.
Results: Lower socioeconomic status was associated with a higher likelihood of obesity, although the strength and pattern of this relationship differed between men and women. Among women, clear inverse gradients were observed across education, income, and the composite SES index. Among men, associations were weaker and less consistent. Adjustment for lifestyle factors attenuated several socioeconomic associations with obesity, although socioeconomic differences remained evident, particularly among women. The composite SES index showed more consistent associations than individual socioeconomic indicators.
Conclusion: Socioeconomic inequalities in obesity persist in South Korea and differ substantially by sex. Associations between socioeconomic status and obesity were attenuated after adjustment for lifestyle factors, although socioeconomic differences remained evident after adjustment. These findings highlight the importance of considering both behavioural and broader structural factors when addressing obesity inequalities.

KEYWORDS

Obesity Socioeconomic Factors Health Behaviour Life Style South Korea

CITATION (Vancouver)

Issayeva Z, Eun KS. Socioeconomic Inequalities in Obesity Among Korean Adults: The Role of Lifestyle Factors in KNHANES 2022–2024. Epidemiology and Health Data Insights. 2026;2(5):ehdi050. https://doi.org/10.63946/ehdi/18958
APA
Issayeva, Z., & Eun, K.-S. (2026). Socioeconomic Inequalities in Obesity Among Korean Adults: The Role of Lifestyle Factors in KNHANES 2022–2024. Epidemiology and Health Data Insights, 2(5), ehdi050. https://doi.org/10.63946/ehdi/18958
Harvard
Issayeva, Z., and Eun, K.-S. (2026). Socioeconomic Inequalities in Obesity Among Korean Adults: The Role of Lifestyle Factors in KNHANES 2022–2024. Epidemiology and Health Data Insights, 2(5), ehdi050. https://doi.org/10.63946/ehdi/18958
AMA
Issayeva Z, Eun KS. Socioeconomic Inequalities in Obesity Among Korean Adults: The Role of Lifestyle Factors in KNHANES 2022–2024. Epidemiology and Health Data Insights. 2026;2(5), ehdi050. https://doi.org/10.63946/ehdi/18958
Chicago
Issayeva, Zhansulu, and Ki-Soo Eun. "Socioeconomic Inequalities in Obesity Among Korean Adults: The Role of Lifestyle Factors in KNHANES 2022–2024". Epidemiology and Health Data Insights 2026 2 no. 5 (2026): ehdi050. https://doi.org/10.63946/ehdi/18958
MLA
Issayeva, Zhansulu et al. "Socioeconomic Inequalities in Obesity Among Korean Adults: The Role of Lifestyle Factors in KNHANES 2022–2024". Epidemiology and Health Data Insights, vol. 2, no. 5, 2026, ehdi050. https://doi.org/10.63946/ehdi/18958

REFERENCES

  1. Ng M, Fleming T, Robinson M, Thomson B, Graetz N, Margono C, et al. Global, regional, and national prevalence of overweight and obesity in children and adults during 1980–2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet. 2014;384(9945):766-81. doi: 10.1016/S0140-6736(14)60460-8
  2. World Health Organization. Obesity and overweight [Internet]. Geneva: World Health Organization; [cited 2026 Jul 10]. Available from: https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight
  3. Popkin BM. Relationship between shifts in food system dynamics and the global nutrition transition. Obes Rev. 2017;18(Suppl 1):3-8. doi: 10.1111/obr.12532
  4. Hruby A, Hu FB. The epidemiology of obesity: a big picture. Pharmacoeconomics. 2015;33(7):673-89. doi: 10.1007/s40273-014-0243-x
  5. McLaren L. Socioeconomic status and obesity. Epidemiol Rev. 2007;29(1):29-48. doi: 10.1093/epirev/mxm001
  6. Dinsa GD, Goryakin Y, Fumagalli E, Suhrcke M. Obesity and socioeconomic status in developing countries: a systematic review. Obes Rev. 2012;13(11):1067-79. doi: 10.1111/j.1467-789X.2012.01017.x
  7. Devaux M, Sassi F. Social inequalities in obesity and overweight in 11 OECD countries. Eur J Public Health. 2013;23(3):464-9. doi: 10.1093/eurpub/cks159
  8. Cho S, Jung JH, Nam GE, Cho IY, Park KY, Jeong SM, et al. 2024 Obesity Fact Sheet in Korea: Prevalence of Obesity, Abdominal Obesity, Obesity Defined by Body Fat Percentage, and Underweight in Adults in Korea from 2013 to 2022. J Obes Metab Syndr. 2025;34(4):405-13. https://doi.org/10.7570/jomes25039
  9. Khang YH, Cho HJ. Socioeconomic inequality in obesity prevalence in Korea. J Epidemiol Community Health. 2006;60(5):428-32. doi: 10.1136/jech.2005.041962
  10. Kim TJ, von dem Knesebeck O. Income and obesity: what is the direction of the relationship? A systematic review and meta-analysis. BMC Public Health. 2012;12:181. doi: 10.1186/1471-2458-12-181
  11. Hwang J, Lee EY, Lee CG. Measuring socioeconomic inequalities in obesity among Korean adults, 1998–2015. Int J Environ Res Public Health. 2019;16(9):1617. doi: 10.3390/ijerph16091617
  12. Choi E, Kim D, Kim S. Socioeconomic inequalities in obesity among Korean women aged 19–79 years: the 2016 Korean Study of Women's Health-Related Issues. Epidemiol Health. 2019;41:e2019005. doi: 10.4178/epih.e2019005
  13. Organisation for Economic Co-operation and Development. OECD Employment Outlook 2022. Paris: OECD Publishing; 2022.
  14. Park S, Rim SJ, Lee JH. Associations between workplace culture and alcohol consumption in South Korea. BMC Public Health. 2017;17:582. doi: 10.1186/s12889-017-4486-9
  15. Braveman PA, Cubbin C, Egerter S, Williams DR, Pamuk E. Socioeconomic disparities in health in the United States: what the patterns tell us. JAMA. 2005;294(22):2879-88. doi: 10.1001/jama.294.22.2879
  16. Stringhini S, Carmeli C, Jokela M, Avendaño M, Muennig P, Guida F, et al. Socioeconomic status and the 25 × 25 risk factors as determinants of premature mortality: a multicohort study and meta-analysis of 1·7 million men and women. Lancet. 2017;389(10075):1229-37. doi: 10.1016/S0140-6736(16)32380-7
  17. Korea Disease Control and Prevention Agency. Korea National Health and Nutrition Examination Survey (KNHANES) [Internet]. Cheongju: KDCA; [cited 2026 Jul 10]. Available from: https://knhanes.kdca.go.kr
  18. WHO Expert Consultation. Appropriate body-mass index for Asian populations and its implications for policy and intervention strategies. Lancet. 2004;363(9403):157-63. doi: 10.1016/S0140-6736(03)15268-3
  19. Chung W, Lim SJ, Lee S. Gender-specific interactions between education and income in relation to obesity among Korean adults. BMJ Open. 2018;8:e020713. doi: 10.1136/bmjopen-2017-020713
  20. Park B, Cho HN, Choi E, Seo DH, Kim S. Weight control behaviors according to body weight status and accuracy of weight perceptions among Korean women: a nationwide population-based survey. PLoS One. 2019;14(12):e0227347. doi: 10.1371/journal.pone.0227347
  21. Sung JH, Son SR, Baek SH, Kim BJ. Association of occupation with daily physical activity and sedentary behaviour among middle-aged Korean workers: a cross-sectional study using KNHANES data. BMJ Open. 2021;11:e055729. doi: 10.1136/bmjopen-2021-055729
  22. Shah D. Healthy worker effect phenomenon. Indian J Occup Environ Med. 2009;13(2):77-9. doi: 10.4103/0019-5278.55123
  23. Stringhini S, Sabia S, Shipley M, Brunner E, Nabi H, Kivimäki M, et al. Association of socioeconomic position with health behaviors and mortality. Lancet. 2010;376(9746):2044-52. doi: 10.1016/S0140-6736(10)61510-1
  24. Swinburn BA, Sacks G, Hall KD, McPherson K, Finegood DT, Moodie ML, et al. The global obesity pandemic: shaped by global drivers and local environments. Lancet. 2011;378(9793):804-14. doi: 10.1016/S0140-6736(11)60813-1

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