The Influence of 7-Day Dietary Nitrate Supplementation on Resting Endothelial Function in Post-Menopausal Women

Objectives: Cardiovascular disease (CVD) is the leading cause of death in women, with the risk being greater following menopause. Consumption of beetroot juice and other nitraterich foods is a promising non‐pharmacological strategy for increasing systemic nitric oxide to improve endothelial function in elderly populations. The purpose of this randomized, placebo‐controlled, crossover clinical trial was to determine if short‐term dietary nitrate supplementation, in the form of beetroot juice, could improve baseline endothelial function in postmenopausal women at two distinct stages of menopause. Methods: Early‐ (1–6 years following their final menstrual period (FMP), n=12) and late‐ (>6 years FMP, n=12) postmenopausal women consumed nitrate‐rich (300 mg/70mL) and nitrate‐depleted beetroot juice (0 mg/70 mL, placebo) for 7 days. Brachial artery flow mediated dilation (FMD)was measured pre‐ and post‐7‐day supplementation. Results: Analyses with general linear models (SPSS) revealed a significant (p<0.05) treatment*time interaction (p=0.047) for baseline FMD (FMDnitrate=4.43±2.80% and FMDplacebo=5.27±2.37%) and post‐supplementation FMD (FMDnitrate=6.47±2.52% and FMDplacebo=5.09±3.01%). Stratification of postmenopausal women into early‐ and lategroups revealed no significant interaction effect. Conclusions: These results suggest that 7 days of nitrate‐rich (300 mg/70 mL) beetroot juice supplementation is sufficient to increase resting endothelial function to a similar extent in postmenopausal women at both postmenopausal stages. Funding Sources: T32DK120509, T32GM108563, UL1 TR002014.