High-nitrate vegetable diet increases plasma nitrate and nitrite concentrations and reduces blood pressure in healthy women

• Published in: Public health nutrition Vol. 18; no. 14; pp. 2669 - 2678
• Main Authors: Ashworth, Ann, Mitchell, Klaus, Blackwell, Jamie R, Vanhatalo, Anni, Jones, Andrew M
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.10.2015
• Subjects: Adolescent; Adult; Blood pressure; Blood Pressure - drug effects; Body mass index; Cross-Over Studies; Diet; Feeding Behavior; Female; Fruits; green leafy vegetables; Health care; Humans; Hypertension; Hypertension - blood; Hypertension - diet therapy; Hypertension - prevention & control; Interventions; Menstruation; Nitrates; Nitrates - blood; Nitrates - pharmacology; Nitrates - therapeutic use; Nitric oxide; nitrites; Nitrites - blood; Plasma; Polyphenols; Reference Values; Research Papers; Risk factors; stroke; Vegetables; Vegetables - chemistry; women; Young Adult; United Kingdom > UK; United States > US; Blood pressure; Nitrate; Vegetables; Nitrite
• ISSN: 1368-9800; 1475-2727; 1475-2727
• DOI: 10.1017/S1368980015000038

Epidemiological studies suggest that green leafy vegetables, which are high in dietary nitrate, are protective against CVD such as stroke. High blood pressure (BP) is a major risk factor for stroke and inorganic nitrate has been shown to reduce BP. The objective of the present study was to test the hypothesis that diets containing high-nitrate (HN) vegetables would increase plasma nitrate and nitrite concentrations and reduce BP in healthy women. A randomized, crossover trial, where participants received HN vegetables (HN diet) or avoided HN vegetables (Control diet) for 1 week. Before and after each intervention, resting BP and plasma nitrate and nitrite concentrations were measured. University of Exeter, UK. Nineteen healthy women (mean age 20 (sd 2) years; mean BMI 22·5 (sd 3·8) kg/m2). The HN diet significantly increased plasma nitrate concentration (before HN diet: mean 24·4 (sd 5·6) µmol/l; after HN diet: mean 61·0 (sd 44·1) µmol/l, P<0·05) and plasma nitrite concentration (before HN diet: mean 98 (sd 91) nmol/l; after HN diet: mean 185 (sd 34) nmol/l, P<0·05). No significant change in plasma nitrate or nitrite concentration was observed after the Control diet. The HN diet significantly reduced resting systolic BP (before HN diet: mean 107 (sd 9) mmHg; after HN diet: mean 103 (sd 6) mmHg, P<0·05). No significant change in systolic BP was observed after the Control diet (before Control diet: mean 106 (sd 8) mmHg; after Control diet: mean 106 (sd 8) mmHg). Consumption of HN vegetables significantly increased plasma nitrate and nitrite concentrations and reduced BP in normotensive women.