Nitrate-Rich Vegetables Increase Plasma Nitrate and Nitrite Concentrations and Lower Blood Pressure in Healthy Adults. Issue 5 (13th April 2016)

• Record Type: Journal Article
• Authors: Jonvik, Kristin L; Nyakayiru, Jean; Pinckaers, Philippe JM; Senden, Joan MG; van Loon, Luc JC; Verdijk, Lex B
• Is Part Of: Journal of nutrition. Volume 146:Issue 5(2016)
• Page Start: 986
• Page End: 993
• Publication Date: 2016-04-13
• Subjects: nitrate -- nitrite -- blood pressure -- bioavailability -- beetroot -- rocket salad -- spinach; Nutrition -- Periodicals; Diet -- Periodicals; 613.205
• DOI: 10.3945/jn.116.229807
• Languages: English
• ISSNs: 0022-3166

Abstract

Abstract: Background: Dietary nitrate is receiving increased attention due to its reported ergogenic and cardioprotective properties. The extent to which ingestion of various nitrate-rich vegetables increases postprandial plasma nitrate and nitrite concentrations and lowers blood pressure is currently unknown. Objective: We aimed to assess the impact of ingesting different nitrate-rich vegetables on subsequent plasma nitrate and nitrite concentrations and resting blood pressure in healthy normotensive individuals. Methods: With the use of a semirandomized crossover design, 11 men and 7 women [mean ± SEM age: 28 ± 1 y; mean ± SEM body mass index (BMI, in kg/m 2 ): 23 ± 1; exercise: 1–10 h/wk] ingested 4 different beverages, each containing 800 mg (∼12.9 mmol) nitrate: sodium nitrate (NaNO3 ), concentrated beetroot juice, a rocket salad beverage, and a spinach beverage. Plasma nitrate and nitrite concentrations and blood pressure were determined before and up to 300 min after beverage ingestion. Data were analyzed using repeated-measures ANOVA. Results: Plasma nitrate and nitrite concentrations increased after ingestion of all 4 beverages ( P < 0.001). Peak plasma nitrate concentrations were similar for all treatments (all values presented as means ± SEMs: NaNO3 : 583 ± 29 μmol/L; beetroot juice: 597 ± 23 μmol/L; rocket salad beverage: 584 ± 24 μmol/L; spinach beverage: 584 ± 23 μmol/L). Peak plasma nitrite concentrations were different between treatments (NaNO3 : 580 ± 58 nmol/L; beetroot juice: 557 ± 57 nmol/L; rocket salad beverage: 643 ± 63 nmol/L; spinach beverage: 980 ± 160 nmol/L; P = 0.016). When compared with baseline, systolic blood pressure declined 150 min after ingestion of beetroot juice (from 118 ± 2 to 113 ± 2 mm Hg; P < 0.001) and rocket salad beverage (from 122 ± 3 to 116 ± 2 mm Hg; P = 0.007) and 300 min after ingestion of spinach beverage (from 118 ± 2 to 111 ± 3 mm Hg; P < 0.001), but did not change with NaNO3 . Diastolic blood pressure declined 150 min after ingestion of all beverages ( P < 0.05) and remained lower at 300 min after ingestion of rocket salad ( P = 0.045) and spinach ( P = 0.001) beverages. Conclusions: Ingestion of nitrate-rich beetroot juice, rocket salad beverage, and spinach beverage effectively increases plasma nitrate and nitrite concentrations and lowers blood pressure to a greater extent than sodium nitrate. These findings show that nitrate-rich vegetables can be used as dietary nitrate supplements. This trial was registered at clinicaltrials.gov as NCT02271633.