Association Between Salt Intake and Body Adiposity in Chinese Population: A Repeated-Measures Cohort Study.

Area of Science:

• Nutritional Epidemiology
• Cardiovascular Health
• Obesity Research

Background:

• Limited longitudinal data exists on the association between salt intake and obesity.
• Previous studies suggest a positive correlation between salt consumption and obesity.
• This study addresses the need for longitudinal evidence on salt intake and adiposity.

Purpose of the Study:

• To investigate the longitudinal association between salt intake and multiple indicators of adiposity.
• To examine the dose-response relationship between salt consumption and obesity metrics.
• To explore the mediating role of body fat mass in this association.

Main Methods:

• Utilized longitudinal data from 7372 adults in a cluster-randomized controlled trial in China.
• Estimated 24-hour salt intake via spot urine samples.
• Assessed adiposity using BMI, BRI, body fat mass, overweight, and central obesity, analyzed with generalized linear mixed-effects models.

Main Results:

• Higher salt intake (≥11.2 g/d) was associated with significantly higher BMI, BRI, body fat mass, and odds of overweight and central obesity compared to lower intake (<8.4 g/d).
• Longitudinally, a reduction in salt intake (>1 g/d) correlated with decreased BMI, BRI, and body fat mass.
• These associations were more pronounced in women and adults under 40, with body fat mass mediating 56.93%-84.73% of the effect.

Conclusions:

• A significant dose-response relationship exists between dietary salt intake and obesity risk.
• Increased body fat mass partially mediates the association between salt intake and adiposity.
• Reducing dietary salt may be a viable strategy to mitigate obesity and associated cardiovascular risks.