Dietary Sodium Density and Blood Pressure in Athletes and Non-Athletes in Young Adulthood and Midlife

Abstract

Current recommendations for the general population limit sodium intake to 2,300 mg/d, however meeting these recommendations may be challenging for athletes, who have greater energy needs. Athletes with greater energy needs are recommended to consume an additional 300-600 mg/h of sodium during prolonged exercise. This recommendation contrasts with guidelines for non-athletes. While the link between sodium and blood pressure (BP) is well-established, studies suggest sodium density, the ratio of sodium to energy consumed, may better predict BP than absolute sodium intake. To our knowledge, no studies have examined these relations in athletes. Hypothesis: We hypothesized that sodium density would be a better indicator of BP when compared to absolute sodium intake and that young athletes would have a higher total sodium intake without a significantly higher BP. Methods: Cross-sectional data were collected from healthy men and women that were stratified into four groups: young collegiate athletes ([YA], n=88, aged 21 ± 2 y), young non-athletes ([YNA], n=36, aged 21 ± 2 y), midlife former collegiate athletes ([MFA], n=82, aged 51 ± 7 y), and midlife non-former athletes ([MNA] n=25, aged 52 ± 7 y). Energy and nutrient intakes were assessed from 3-day dietary records. Anthropometric and BP measurements were collected. Group differences were assessed using a one-way ANOVA with Tukey post-hoc tests. Associations between absolute sodium and sodium density and BP were assessed using Pearson correlations. Results: YA (4102 ± 1490 mg) had a significantly higher sodium intake when compared to YNA (3305 ± 1072 mg), MFA (3159 ± 1154 mg), and MNA (2955 ± 956 mg) (p<0.05 for all). Systolic BP (SBP) was higher in MFA (130 ± 17 mmHg; p<0.05) compared to YA (120 ± 13 mmHg) and YNA (116 ± 13 mmHg). Absolute sodium intake and SBP were positively correlated in YA (r=0.26, p=0.02), YNA (r=0.43, p=0.01) and MFA (r=0.26, p=0.02) but not MNA (r=0.04, p=0.84); however, when corrected for energy intake, these correlations were no longer statistically significant for all groups. Conclusion: These data suggest a weak association between absolute sodium intake and BP in YA. However, when corrected for energy intake this association was no longer present. This may not be specific to YA as this association was also seen in YNA and MFA. Our results highlight the importance of examining both absolute sodium intake and sodium density as it relates to BP in populations with increased energy needs. NIH (DP5 OD031833, R01 HL145055, 2UL1TR001436). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.