Higher intakes of sodium may contribute to weight gain. The primary aim of this systematic review and meta-analysis was to examine the relationship between dietary sodium intake and measures of adiposity in children and adults. Given the previous link between sodium intake and the consumption of sugar-sweetened beverages (SSBs), which are a known risk factor for obesity, a secondary aim examining the relationship between sodium intake and SSB consumption was assessed. A systematic literature search identified cross-sectional and longitudinal studies and randomised controlled trials (RCTs) which reduced dietary sodium (≥3 months). Meta-analysis was performed for outcomes with ≥3 studies. Cross-sectionally higher sodium intakes were associated with overweight/obesity in adults (5 studies; n=11,067; (OR) 1.74, 95%CI 1.43,2.13) and in children (3 studies; n=3625, OR=3.29,2.25, 4.80); and abdominal obesity (5 studies; n=19,744; OR=2.04, 1.72, 2.42) in adults. Overall, associations remained in sensitivity analyses which adjusted for energy. Findings from longitudinal studies were inconsistent. RCTs in adults indicated a trend for lower body weight on reduced sodium compared to control diets (15 studies; n=5274; -0.29 kg, -0.59,0.01; P=0.06), however it is unclear if energy intakes were also altered on reduced sodium diets. Among children higher sodium intakes were associated with higher intake of SSBs (4 studies, n=10,329, b=22, 16,26 g/d), no studies were retrieved for adults. Overall there was a lack of high quality studies retrieved. Whilst cross-sectional evidence indicates sodium intake was positively associated with adiposity, these findings have not been clearly confirmed by longitudinal studies or randomised controlled trials.