The Relationship between Daily Sodium Intake and Obesity in Korean Adults

Background World health organization (WHO) recommended daily sodium intake less than 2 g. To assess the validity of WHO recommendation, we investigated the relationship between daily sodium intake and obesity. Methods A total of 14,694 participants aged ≥19 years who had no missing data for nutrition, chronic disease, health behavior, economic status and laboratory findings from the 5th Korean National Health and Nutrition Examination Survey (KNHANES-V), which was performed from 2010 to 2012. Obesity was defined as having a body mass index of 25 kg/m2 or higher. Daily sodium intake was calculated from 24 hour recall and divided into five categories (< 2 g, 2-4 g, 4-6 g, 6-8 g, ≥8 g). The association between daily sodium intake and obesity was analyzed using multiple logistic regressions. Results Higher sodium intake in men had an increased risk of obesity with odds ratios (ORs) of 1.27 for 2-4 g intake (95% confidence interval [CI], 0.97-1.67), 1.40 for 4-6 g intake (95% CI, 1.07-1.85), 1.41 for 6-8 g intake (95% CI, 1.05-1.89), and 1.61 for ≥8 g intake (95% CI, 1.19-2.18), compared to men with less than 2 g intake, after adjusting for confounding factors. The P value for trend of ORs in each group for men was 0.020. In women, compared to the lesser than 2 g intake, only ≥8 g intake group had an OR of 1.28 (95% CI, 1.02-1.62) without showing significant P for trend (P value for trend=0.221) Conclusions We found that sodium intake more than 2 g per day was independently related to the increased risk of obesity in men. Therefore, to minimize the risk of obesity, we suggest taking sodium less than 2 g per day.