A Reversal of the Association between Education Level and Obesity Risk during Ageing: A Gender-Specific Longitudinal Study in South Korea

Abstract

This study aimed to examine and quantify obesity risk across different education levels during ageing using the dataset of a nationally representative longitudinal survey. A total of 45,391 observations of 9991 individuals aged ≥45 years were included in this study. Obesity was defined as a body mass index of ≥25, according to a guideline for Asians by the World Health Organization, and education level was grouped into three categories. Socio-demographics, lifestyles, and health conditions were used as covariates. Adjusted odds ratios and predicted probabilities of obesity were computed and adjusted for a complex survey design. With respect to gender, education level and age were significantly associated with obesity risk, and the association was stronger in women than in men. Furthermore, education level was negatively associated with obesity risk in the middle age in each gender. However, the association became positive in the old age, specifically among highly educated women. Therefore, policy efforts to reduce obesity risk and the resulting education gradients should be established based on studies considering their old age. Further longitudinal studies are required to examine whether these findings are valid in other socio-cultural or economic settings.

Do associations between education and obesity vary depending on the measure of obesity used? A systematic literature review and meta-analysis

“…In total, 85 studies reported on associations between education and obesity defined using BMI ( Table S3 ). There were eight longitudinal studies (follow-ups were five ( Camões et al, 2010 ), 10 ( Chung and Kim, 2020 ), 13 (von Hippel & Lynch, 2014) , 14 ( Coogan et al, 2012 ), 23 ( Salsberry and Reagan, 2009 ), 29 (Cohen, Rehkopf, Deardorff, & Abrams, 2013b) , 33 ( Salonen et al, 2009 ) and 36 years ( Kim, 2016 )). Six studies reported results of multiple countries ( Devaux & Sassi, 2013 ; Drewnowski et al, 2005 ; Hughes et al, 2017 ; Klumbiene et al, 2004 ; Roskam et al, 2010 ; Sarlio-Lähteenkorva et al, 2006 ).…”

Differences in Body Mass Index Trajectories and Their Classification, Sociodemographic Characteristics, and Health Behaviors between People with and without Disabilities Using Korea Health Panel Survey Data

“…According to the results of this study, the relationship between education and the BMI of people with disabilities was not significant. Previous studies [ 12 , 40 , 41 ] reported that the BMI values of people with lower education fell within the higher range compared to people with higher education. However, studies on the mechanism of the effect of education level and the BMI of people with disabilities could not be confirmed.…”

Education, income, and obesity: A nationwide Chinese twin study

“…Many studies have explored the relationship between SES (education and income in this study) and obesity, and evidence has shown that SES was strongly related to obesity in prospective cohort studies (29‐32). The framework of social determinants of health suggests that material, psychosocial, and behavioral factors contribute to the explanation of SES inequalities in obesity (33).…”