Nutrition Research and Practice

The Korean Nutrition Society (한국영양학회)
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The association between dietary sodium intake and obesity in adults by sodium intake assessment methods: a review of systematic reviews and re-meta-analysis

  • Jounghee Lee (Department of Food and Nutrition, Kunsan National University) ;
  • Cheongmin Sohn (Department of Food and Nutrition, Wonkwang University) ;
  • Oh-Yoen Kim (Department of Food Science and Nutrition, Dong-A University) ;
  • Young-Min Lee (Department of Practical Science Education, Gyeongin National University of Education) ;
  • Mi Ock Yoon (Nutrition Information Center, Korean Nutrition Society) ;
  • Myoungsook Lee (Department of Food and Nutrition, School of Bio-Health Convergence, Health & Wellness College, Sungshin Women's University)
  • Received : 2022.12.07
  • Accepted : 2023.01.17
  • Published : 2023.04.01
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Abstract

BACKGROUND/OBJECTIVES: The scientific evidence of a sodium-obesity association is limited by sodium intake assessments. Our specific aim is to synthesize the association between dietary sodium intake and obesity across the sodium intake assessments as evidenced by systematic reviews in adults. SUBJECTS/METHODS: A systematic search identified systematic reviews comparing the association of dietary sodium intakes with obesity-related outcomes such as body mass index (BMI), body weight, waist circumference, and risk of (abdominal) obesity. We searched PubMed on October 24, 2022. To assess the Risk of Bias in Systematic Reviews (ROBIS), we employed the ROBIS tool. RESULTS: This review included 3 systematic reviews, consisting of 39 unique observational studies (35 cross-sectional studies and 4 longitudinal studies) and 15 randomized controlled trials (RCTs). We found consistently positive associations between dietary sodium intake and obesity-related outcomes in cross-sectional studies. Studies that used 24-h urine collection indicated a greater BMI for those with higher sodium intake (mean difference = 2.27 kg/m2; 95% confidence interval [CI], 1.59-2.51; P < 0.001; I2 = 77%) compared to studies that used spot urine (mean difference = 1.34 kg/m2; 95% CI, 1.13-1.55; P < 0.001; I2 = 95%) and dietary methods (mean difference = 0.85 kg/m2; 95% CI, 0.1-1.51; P < 0.05; I2 = 95%). CONCLUSIONS: Quantitative synthesis of the systematic reviews has shown that cross-sectional associations between dietary sodium intake and obesity outcomes were substantially different across the sodium intake assessments. We need more high-quality prospective cohort studies and RCTs using 24-h urine collection to examine the causal effects of sodium intake on obesity.

Keywords

Acknowledgement

This work was supported by the Korea Institute of Planning and Evaluation for Technology in Food, Agriculture and Forestry (IPET) through the High Value-added Food Technology Development Program, funded by the Ministry of Agriculture, Food and Rural Affairs (MAFRA) (321029-05).

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