scholarly journals Dietary nitrate and blood pressure: evolution of a new nutrient?

2017 ◽  
Vol 30 (2) ◽  
pp. 208-219 ◽  
Author(s):  
Ann Ashworth ◽  
Raul Bescos
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Daily Intake ◽  
Epidemiological Studies ◽  
Leafy Vegetables ◽  
Sufficient Evidence ◽  
Potential Health ◽  
Dietary Nitrate ◽  
Green Leafy Vegetables ◽  
The Uk

AbstractDietary nitrate is mainly obtained from vegetables, especially green leafy vegetables and beetroot. As a result of early research, dietary nitrate is currently viewed as a contaminant linked to increased risks of stomach cancer and methaemoglobinaemia. Consequently, nitrate levels are restricted in certain vegetables and in water supplies to ensure exposure levels remain below an acceptable daily intake of 3·7 mg/kg per d. The average nitrate intake in the UK is approximately 70 mg/d, although some population groups, such as vegetarians, may consume three times that amount. However, recent studies in the last decade suggest that dietary nitrate can significantly reduce systolic blood pressure via the nitrate–nitrite–NO pathway. A small, downward shift in systolic blood pressure across the population could significantly reduce the incidence of hypertension and mortality from CVD such as stroke. Interestingly, vegetarians tend to have lower levels of blood pressure than omnivores and epidemiological studies suggest that vegetarians have lower risks of CVD. Recent evidence is mainly focused on the acute effects of dietary nitrate supplementation and there is a lack of data looking at the chronic effects of high nitrate consumption in humans. Nevertheless, due to potential health benefits, some authors are recommending that nitrate should be considered as a nutrient necessary for health, rather than as a contaminant which needs to be restricted. This review will discuss the emerging role of dietary nitrate in the control of blood pressure and whether there is sufficient evidence to state that nitrate is a ‘new’ nutrient.

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

2015 ◽  
Vol 18 (14) ◽  
pp. 2669-2678 ◽  
Author(s):  
Ann Ashworth ◽  
Klaus Mitchell ◽  
Jamie R Blackwell ◽  
Anni Vanhatalo ◽  
Andrew M Jones
Keyword(s):  
Blood Pressure ◽  
Control Diet ◽  
Epidemiological Studies ◽  
Leafy Vegetables ◽  
Nitrite Concentration ◽  
Green Leafy Vegetables ◽  
Healthy Women ◽  
Significant Change ◽  
Plasma Nitrate ◽  
Nitrate And Nitrite

AbstractObjectiveEpidemiological 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.DesignA 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.SettingUniversity of Exeter, UK.SubjectsNineteen healthy women (mean age 20 (sd2) years; mean BMI 22·5 (sd3·8) kg/m2).ResultsThe HN diet significantly increased plasma nitrate concentration (before HN diet: mean 24·4 (sd5·6) µmol/l; after HN diet: mean 61·0 (sd44·1) µmol/l,P<0·05) and plasma nitrite concentration (before HN diet: mean 98 (sd91) nmol/l; after HN diet: mean 185 (sd34) 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 (sd9) mmHg; after HN diet: mean 103 (sd6) mmHg,P<0·05). No significant change in systolic BP was observed after the Control diet (before Control diet: mean 106 (sd8) mmHg; after Control diet: mean 106 (sd8) mmHg).ConclusionsConsumption of HN vegetables significantly increased plasma nitrate and nitrite concentrations and reduced BP in normotensive women.

scholarly journals Determinants and Suitability of Carotenoid Reflection Score as a Measure of Carotenoid Status

Nutrients ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 113 ◽  
Author(s):  
Elaine Rush ◽  
Isaac Amoah ◽  
Tung Diep ◽  
Shabnam Jalili-Moghaddam
Keyword(s):  
Body Size ◽  
Health Outcomes ◽  
Daily Intake ◽  
Leafy Vegetables ◽  
Carotenoid Concentration ◽  
Dairy Foods ◽  
Green Leafy Vegetables ◽  
Positive Correlations ◽  
Dark Green ◽  
Negative Health Outcomes

Carotenoids, orange-coloured pigments found in vegetables, fruit, eggs and dairy foods, act as antioxidants and vitamin A precursors in the human body. Skin carotenoid concentration is a biomarker of vegetable and fruit intake. The aim was to identify determinants of skin carotenoid concentration by measuring “Veggie Meter™” carotenoid reflection spectroscopy scores (CRS) from the fingertip of adults with a range of ages, ethnicity and body size. Frequencies of daily intake of vegetables and fruit and weekly intake of pumpkin and carrot, dark green leafy vegetables (DGLV), eggs (yolk), and dairy were determined from a self-completed food-frequency-questionnaire. A total of 571 (324 Women, 247 Men) adults, aged 16 to 85 years, completed measurements. The CRS ranged from 83 to 769, with a median of 327. Women and men did not score differently. For all participants there were negative correlations of CRS with weight (r = −0.312) and BMI (r = −0.338) and positive correlations with weekly intakes of DGLV (r = 0.242) and carrots and pumpkin (r = 0.202). Based on a review of health outcomes associated with plasma carotenoids, 82% of the participants in the current study are at moderate risk, or more, of negative health outcomes. Determinants of carotenoid status were body size, intake of DGLV, carrots and pumpkin, and ethnicity.

Measuring Blood Pressure

Nursing OSCEs ◽  
2012 ◽  
Author(s):  
Kate Devis
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Pressure Measurement ◽  
Gold Standard ◽  
Blood Pressure Measurement ◽  
Maximum Pressure ◽  
Pressure Measurements ◽  
Health Care Settings ◽  
Pressure Cuff ◽  
The Uk

Blood pressure measurements are one part of a circulatory assessment (Docherty and McCallum 2009). Treatments for raised or low blood pressure may be initiated or altered according to blood pressure readings; therefore correct measurement and interpretation of blood pressure is an important nursing skill. Blood pressure should be determined using a standardized technique in order to avoid discrepancies in measurement (Torrance and Serginson 1996). Both manual and automated sphygmomanometers may be used to monitor blood pressure. The manual auscultatory method of taking blood pressure is considered the gold standard (MRHA 2006), as automated monitoring can give false readings (Coe and Houghton 2002), and automated devices produced by different manufacturers may not give consistent figures (MRHA 2006). So, although automated sphygmomanometers are in common use within health care settings in the UK, the skill of taking blood pressure measurement manually is still required by nurses. As a fundamental nursing skill, blood pressure measurement, using manual and automated sphygmomanometers, and interpretation of findings are often assessed via an OSCE. Within this chapter revision of key areas will allow you to prepare thoroughly for your OSCE, in terms of practical skill and understanding of the procedure of taking blood pressure. Blood pressure is defined as the force exerted by blood against the walls of the vessels in which it is contained (Docherty and McCallum 2009). A blood pressure measurement uses two figures—the systolic and diastolic readings. The systolic reading is always the higher figure and represents the maximum pressure of blood against the artery wall during ventricular contraction. The diastolic reading represents the minimum pressure of the blood against the wall of the artery between ventricular contractions (Doughetry and Lister 2008). You will need to be able to accurately identify systolic and diastolic measurements during your OSCE. When a blood pressure cuff is applied to the upper arm and inflated above the level of systolic blood pressure no sounds will be detected when listening to the brachial artery with a stethoscope. The cuff clamps off blood supply. As the cuff is deflated a noise, which is usually a tapping sound, will be heard as the pressure equals the systolic blood pressure —this is the first Korotkoff ’s sound.

The effects of dietary nitrate on blood pressure and endothelial function: a review of human intervention studies

2013 ◽  
Vol 26 (2) ◽  
pp. 210-222 ◽  
Author(s):  
Ditte A. Hobbs ◽  
Trevor W. George ◽  
Julie A. Lovegrove
Keyword(s):  
Blood Pressure ◽  
Endothelial Function ◽  
Systolic Blood Pressure ◽  
Intervention Studies ◽  
Blood Pressure Reduction ◽  
Oral Bacteria ◽  
Human Intervention ◽  
Dietary Nitrate ◽  
Beneficial Effects ◽  
Healthy Humans

Evidence has accumulated in recent years that suggests that nitrate from the diet, particularly vegetables, is capable of producing bioactive NO in the vasculature, following bioconversion to nitrite by oral bacteria. The aim of the present review was to consider the current body of evidence for potential beneficial effects of dietary nitrate on blood pressure and endothelial function, with emphasis on evidence from acute and chronic human intervention studies. The studies to date suggest that dietary nitrate acutely lowers blood pressure in healthy humans. An inverse relationship was seen between dose of nitrate consumed and corresponding systolic blood pressure reduction, with doses of nitrate as low as 3 mmol of nitrate reducing systolic blood pressure by 3 mmHg. Moreover, the current studies provide some promising evidence on the beneficial effects of dietary nitrate on endothelial function.In vitrostudies suggest a number of potential mechanisms by which dietary nitrate and its sequential reduction to NO may reduce blood pressure and improve endothelial function, such as: acting as a substrate for endothelial NO synthase; increasing vasodilation; inhibiting mitochondrial reactive oxygen species production and platelet aggregation. In conclusion, the evidence for beneficial effects of dietary nitrate on blood pressure and endothelial function is promising. Further long-term randomised controlled human intervention studies assessing the potential effects of dietary nitrate on blood pressure and endothelial function are needed, particularly in individuals with hypertension and at risk of CVD.

scholarly journals Influence of Green Leafy Vegetables in Diets with an Elevated ω-6:ω-3 Fatty Acid Ratio on Rat Blood Pressure, Plasma Lipids, Antioxidant Status and Markers of Inflammation

Nutrients ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 301 ◽  
Author(s):  
Melissa Johnson ◽  
Wendell McElhenney ◽  
Marceline Egnin
Keyword(s):  
Blood Pressure ◽  
Fatty Acid ◽  
Disease Risk ◽  
Leafy Vegetables ◽  
Fatty Acid Ratio ◽  
Plasma Adiponectin ◽  
Green Leafy Vegetables ◽  
Pressure Plasma ◽  
Acid Ratio ◽  
Plasma Antioxidant Capacity

The typical Western dietary pattern has an elevated ω-6:ω-3 fatty acid ratio (FAR), which may exacerbate the risk of chronic disease. Conversely, the consumption of diets containing green leafy vegetables (GLVs) have been demonstrated to attenuate disease risk. This study investigated the effects of collard greens (CG), purslane (PL) and orange flesh sweetpotato greens (SPG) on measures of disease risk in rats fed diets with a 25:1 ω-6:ω-3 FAR. Male spontaneously hypertensive rats (SHRs) were randomly assigned to four dietary groups (n = 10/group) with a 25:1 ω-6:ω-3 FAR. Experimental diets contained 4% (dried weight) CG, PL or SPG. Dietary intake, body weight, blood pressure, plasma adiponectin, high sensitivity C-reactive protein (hsCRP), oxygen radical absorbance capacity and lipid profile were determined using standardized procedures. Following a 6-week consumption period, systolic blood pressure, plasma adiponectin, total and low-density lipoprotein (LDL) cholesterol decreased following the consumption of diets containing GLVs. While hsCRP increased in SHRs fed diets containing CG and PL, plasma antioxidant capacity was significantly reduced (p < 0.05) with the consumption of diets containing the GLVs. These findings suggest that CG, PL and SPG have the potential to decrease risks for cardiovascular disease (CVD) associated with the consumption of diets with an elevated ω-6:ω-3 FAR.

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