ASSOCIATION BETWEEN SODIUM INTAKE AND OBESITY AND ABDORMINAL OBESITY IN KOREAN ADULTS: ANALYSIS OF THE KNHANES 2009-2011

INTRODUCTION: Sodium intake of Korean, which is more than twice as recommended by the WHO, is a very important public health problem in Korea. High sodium intake is associated with hypertension. Obesity is also closely related with cardiovascular disease, including hypertension. This study investigated the association between high sodium intake and obesity and abdominal obesity in Korea.

METHODS: This study included 15,531 subjects (≥20 years, male: 6,796, female: 8,735) who participated in the Korean National Health and Nutrition Examination Survey (KNHANES) 2009-2011. The 24-hour sodium intake was estimated using spot urinary sodium concentration (mg/day). Multivariate logistic regression analysis was performed to assess the risk of obesity and abdominal obesity after adjusting of age, education, daily energy intake, smoking status, daily alcohol intake, weekly physical activity, soft drink intake, household income and systolic blood pressure.

RESULTS: The prevalence rates of obesity (body mass index ≥ 25 kg/m²) were 36.5% in male and 28.5% in female and those of abdominal obesity (waist circumference ≥90 cm for male and ≥85 cm for female) were 25.3% in male and 24.8% in female, respectively. The multivariate-adjusted odds ratio (mOR) for obesity (body mass index ≥ 25 kg/m²) in adults with the highest quintile (Q5) of sodium intake, compared with the lowest quintile, was 1.86 (95% confidence interval (CI): 1.49~2.33) in male and 1.92 (CI: 1.59~2.32) in female, respectively, and both showed significant dose–response associations (p for trend <0.0001). The mOR for abdominal obesity of the Q5 was 1.71 (CI: 1.38~2.10) in male and 1.68 (CI: 1.39~2.04) in female, and a significant dose–response association (p for trend <0.0001) was observed.

CONCLUSIONS: This study demonstrates that high sodium was associated with the risk of obesity and abdominal obesity in Korean adults.