Dietary sodium suppresses high‐fat diet weight gain in C57Bl/6J mice

• DOI: 10.1096/fasebj.27.1_supplement.1153.3
• Publication Date: 2021-06-16T10:12:44Z
• Authors: Nicole A. Pearson; Nicole K. Littlejohn; Michael L. Lutter; Justin L. Grobe
• Keywords: 2. Zero hunger; 0303 health sciences; 03 medical and health sciences

To examine the synergistic effects of dietary sodium and fat on weight gain, male C57Bl/6J mice (9 wk) were placed (n=5 each) on a 45% (kcal) high‐fat diet (HFD, Bio‐Serv) with 0.25, 0.5, 1, 2, or 4% sodium, or standard chow (Teklad 7013). While baseline body masses were indistinguishable, the rate of weight gain was increased with HFD, and this was reduced with increasing sodium content (chow = 0.52±0.02, vs HFD+0.25% = 1.88±0.17, HFD+4% = 0.70±0.10 g/week). NMR at 4 weeks revealed adipose mass gains that paralleled body mass gains, with increased sodium preventing gains in a dose‐dependent fashion. These effects were maintained and confirmed by tissue masses at 10 weeks of treatment. Further, it was determined that the adipose gains were made primarily in the inguinal and perigenital fat, with no changes in interscapular fat. Caloric intake at ten weeks of treatment was similar across groups (11.4 to 15.9 kcal/day), while sodium intake correlated tightly with diet content (0.284 to 5.942 mEq/day), suggesting that the mice regulated food intake based on caloric content rather than sodium content. These data support the hypothesis that dietary sodium is a positive regulator of metabolic rate. Ongoing studies are focused on determining whether these effects are mediated by suppression of circulating renin, and whether new lower (renin‐inducing) USDA sodium intake guidelines will have unintended metabolic consequences.