Diets rich in green, leafy vegetables have been shown to lower blood pressure (BP) and reduce the risk of cardiovascular disease. Green, leafy vegetables and beetroot are particularly rich in inorganic nitrate. Dietary nitrate supplementation, via sequential reduction to nitrite and NO, has previously been shown to lower BP and improve endothelial function in healthy humans. We sought to determine if supplementing dietary nitrate with beetroot juice, a rich source of nitrate, will lower BP and improve endothelial function and insulin sensitivity in individuals with type 2 diabetes (T2DM). Twenty-seven patients, age 67.2±4.9 years (18 male), were recruited for a double-blind, randomized, placebo-controlled crossover trial. Participants were randomized to begin, in either order, a 2-week period of supplementation with 250ml beetroot juice daily (active) or 250ml nitrate-depleted beetroot juice (placebo). At the conclusion of each intervention period 24-h ambulatory blood pressure monitoring, tests of macro- and microvascular endothelial function, and a hyperinsulinemic isoglycemic clamp were performed. After 2 weeks administration of beetroot juice mean ambulatory systolic BP was unchanged: 134.6±8.4mmHg versus 135.1±7.8mmHg (mean±SD), placebo vs active-mean difference of -0.5mmHg (placebo-active), p=0.737 (95% CI -3.9 to 2.8). There were no changes in macrovascular or microvascular endothelial function or insulin sensitivity. Supplementation of the diet with 7.5mmol of nitrate per day for 2 weeks caused an increase in plasma nitrite and nitrate concentration, but did not lower BP, improve endothelial function, or improve insulin sensitivity in individuals with T2DM.

Hypothesis: Beetroot juice increases the exercise tolerance of patients with chronic lung disease.

Using the already established pulmonary rehabilitation model, we aim to split the group of 8 into 2 groups, each group taking 500ml of beetroot juice 24 hours before there class on alternate (differing) weeks to see if it improves their overall exercise tolerance.

Cardiovascular diseases, still the leading cause of mortality in the world, are closely related to vascular function. Older subjects are more susceptible to endothelial dysfunction and therefore it is important to define possible preventive or support strategies, such as consumption of foods with health-promoting effects. This systematic review aims to summarize the currently available evidence on acute or chronic trials testing the effect of selected plant-based foods on vascular function parameters in older subjects, and consider plausible mechanisms that may support the main findings. A total of 15 trials were included and analyzed, testing the effects of beetroot, plum, blueberry, and vegetable oils. We found some interesting results regarding markers of vascular reactivity, in particular for beetroot, while no effects were found for markers of arterial stiffness. The amelioration of vascular function seems to be more related to the restoration of a condition of nitric oxide impairment, exacerbated by diseases or hypoxic condition, rather than the enhancement of a physiological situation, as indicated by the limited effects on healthy older subjects or in control groups with young subjects. However, the overall set of selected studies is, in any case, rather limited and heterogeneous in terms of characteristics of the studies, indicating the need for additional high-quality intervention trials to better clarify the role of vegetable foods in restoring and/or improving vascular function in order to better elucidate the mechanisms through which these foods may exert their vascular health benefits in older subjects.

Most intervention studies investigating the effects of ergogenic aids (EAs) on sports performance have been carried out in the male population. Thus, the aim of this systematic review and meta-analysis was to summarize the effects in the existing literature of EAs used by female athletes on performance. A literature research was conducted, and a descriptive analysis of the articles included in the systematic review was carried out. Meta-analyses could be performed on 32 of the included articles, evaluating performance in strength, sprint, and cardiovascular capacity. A random-effects model and the standardized mean differences (SMD) ± 95% confidence intervals (CI) were reported. The results showed that caffeine helped to improve jumping performance, isometric strength values, and the number of repetitions until failure. Caffeine and sodium phosphate helped to improve sprint performance. Aerobic tests could be improved with the use of taurine, caffeine, and beta-alanine. No conclusive effects of beetroot juice, polyphenols, or creatine in improving aerobic performance were shown. In terms of anaerobic variables, both caffeine and sodium phosphate could help to improve repeated sprint ability. More studies are needed in female athletes that measure the effects of different EAs on sports performance, such as beetroot juice, beta-alanine or sodium phosphate, as the studies to date are scarce and there are many types of EA that need to be further considered in this population, such as creatine and taurine. © 2022 by the authors.

Chronic heart failure (CHF) impairs skeletal muscle O2 transport and utilization leading to restricted physical capacity. Dietary nitrate supplementation has been shown to improve vascular function, reduce the O2 cost of muscle contraction and enhance exercise tolerance (Tlim) in both healthy and clinical populations (e.g., COPD). We tested the hypothesis that dietary nitrate would improve locomotor muscle O2 delivery-utilization matching and Tlim in CHF patients. Methods: Nine males with CHF (ejection fraction=33±6%) consumed either nitrate-rich (∼12 mmol nitrate; beetroot juice) or nitrate-depleted beetroot juice (placebo) for 8 days. Mean arterial pressure (MAP), central hemodynamics by impedance cardiography (stroke volume, heart rate and cardiac output), pulmonary oxygen uptake (VO2) and muscle oxygenation by near-infrared spectroscopy were determined at rest and during low- and high-intensity “step” exercise tests. Results: No differences were observed between placebo vs. beetroot juice for resting and exercising MAP, central hemodynamics or muscle oxygenation (p>0.05). The O2 cost of exercise during both low- (placebo: 0.88±0.19 vs. beetroot juice: 0.94±0.24 l/min) and high-intensity (1.33±0.30 vs. 1.36±0.31 l/min) cycling and Tlim (489±194 vs. 485±173 s) were also unaffected by beetroot juice (p>0.05). Conclusions: Contrary to the hypothesis, 8 days of dietary nitrate supplementation did not enhance skeletal muscle O2 delivery-utilization matching or exercise tolerance in CHF patients. Whether longer treatment duration and/or higher doses are therapeutically effective in this patient population remains to be determined.

Six days of dietary nitrate supplementation in the form of beetroot juice (~0.5 L/d) has been reported to reduce pulmonary oxygen uptake (VO₂) during submaximal exercise and increase tolerance of high-intensity work rates, suggesting that nitrate can be a potent ergogenic aid. Limited data are available regarding the effect of nitrate ingestion on athletic performance, and no study has investigated the potential ergogenic effects of a small-volume, concentrated dose of beetroot juice. The authors tested the hypothesis that 6 d of nitrate ingestion would improve time-trial performance in trained cyclists. Using a double-blind, repeated-measures crossover design, 12 male cyclists (31 ± 3 yr, VO_2peak = 58 ± 2 ml · kg^-1 · min-^-1, maximal power [W_max] = 342 ± 10 W) ingested 140 ml/d of concentrated beetroot (~8 mmol/d nitrate) juice (BEET) or a placebo (nitrate-depleted beetroot juice; PLAC) for 6 d, separated by a 14-d washout. After supplementation on Day 6, subjects performed 60 min of submaximal cycling (2 × 30 min at 45% and 65% W_max, respectively), followed by a 10-km time trial. Time-trial performance (953 ± 18 vs. 965 ± 18 s, p < .005) and power output (294 ± 12 vs. 288 ± 12 W, p < .05) improved after BEET compared with PLAC supplementation. Submaximal VO₂ was lower after BEET (45% W_max = 1.92 ± 0.06 vs. 2.02 ± 0.09 L/min, 65% W_max 2.94 ± 0.12 vs. 3.11 ± 0.12 L/min) than with PLAC (main effect, p < .05). Wholebody fuel selection and plasma lactate, glucose, and insulin concentrations did not differ between treatments. Six days of nitrate supplementation reduced VO₂ during submaximal exercise and improved time-trial performance in trained cyclists.

RATIONALE:

A primary goal of therapy for patients with peripheral artery disease (PAD) and intermittent claudication is increased ambulatory function. Supervised exercise rehabilitation was recently shown to confer superior walking benefits to pharmacological or surgical interventions. Increases in plasma inorganic nitrite, via oral nitrate, have been shown to increase exercise performance in both human and animal models, especially in hypoxic conditions.

OBJECTIVE:

To determine whether a 36-session exercise rehabilitation program while consuming oral inorganic nitrate (4.2 mmol concentrated beetroot juice) would produce superior benefits over exercise plus placebo in pain-free walking and markers of increased skeletal muscle perfusion in patients with PAD and intermittent claudication.

METHODS AND RESULTS:

This was a randomized, double-blind, per-protocol study design. After the 12-week protocol, claudication onset time on a maximal treadmill test increased by 59.2±57.3 s for the exercise plus placebo group (n=13) and by 180.3±46.6 s for the exercise plus beetroot juice group (n=11; P≤0.05). This produced a between treatment medium to large standardized effect size (Cohen d) of 0.62 (95% CI, -0.23 to +1.44). The data for 6-minute walk distance showed a similar pattern with increases of 24.6±12.1 and 53.3±19.6 m ( P≤0.05) in the exercise plus placebo and exercise plus beetroot juice groups, respectively. Measures of gastrocnemius perfusion, including ankle-brachial index, peak reactive hyperemic blood flow, and tissue deoxygenation characteristics, during exercise (assessed my near-infrared spectroscopy) all changed significantly for the exercise plus beetroot juice group with moderate-to-large effect sizes over exercise plus placebo changes.

CONCLUSIONS:

Although it is premature to speculate on overall clinical utility of a nitrate-based therapy for PAD, this early pilot study evidence is encouraging. Specifically, our data suggests that increasing plasma nitrite before exercise may allow PAD subjects to train with less pain, at higher workloads for longer durations at each training session, thereby maximizing the beneficial peripheral vascular and skeletal muscle adaptations.

CLINICAL TRIAL REGISTRATION:

URL:

http://www.clinicaltrials.gov . Unique identifier: NCT01684930 and NCT01785524.

Acute consumption of dietary nitrate (as beetroot juice) has been shown to improve exercise capacity in athletes, healthy adults and subjects with both peripheral vascular disease or COPD. Many patients with dilated cardiomyopathy have reduced exercise capacity, The investigators hypothesized that acute nitrate consumption might increase incremental shuttle walk test (ISWT) distance in dilated cardiomyopathy subjects compared to a placebo beetroot juice.

OBJECTIVE:

The purpose of this study is to comparatively evaluate the effect of discoloration of nanohybrid composite by four different phytopigments.

MATERIALS AND METHODS:

Fifty disk-shaped samples of nanohybrid (3M Filtek Z350) resin composites were prepared using an acrylic template of dimension 5 mm × 3 mm. They were randomly divided into five groups and immersed in solutions of tomato powder, beetroot powder, java plum powder, and turmeric powder. Distilled water was used as the control group. The samples were placed in respective solutions for 3 h daily and stored in artificial saliva for the rest of the day for 28 days. Color values (L*, a*, b*) were measured by colorimeter using the CIE L*a*b* system at the end of the 7th and 28th days of immersion. Color differences ΔE*ab were statistically analyzed.

RESULTS:

All the samples showed a change in color of nanohybrid composite resin to varying degrees. The mean ΔE*ab value obtained with beetroot solution was the highest among all the groups at the end of the 7th and 28th days, depicting that beetroot solution showed maximum mean color variation, followed by java plum solution, turmeric solution, and tomato solution.

CONCLUSION:

All the phytopigments used in this study have the potential to discolor the nanohybrid composite resin, with beetroot causing the most severe discoloration.

Emerging evidence suggests that increasing dietary nitrate intake may be an effective approach to reduce blood pressure. Beetroot juice is often used to supplement dietary nitrate, whereas nitrate intake levels from habitual diet are low. An increase in the habitual intake of nitrate-rich vegetables may represent an alternative to nitrate supplementation. However, the effectiveness and acceptability of a nitrate–rich-vegetables diet remain to be established. The aim was to investigate the effect and feasibility of two different intervention strategies to increase dietary nitrate intake, on plasma nitrate/nitrite concentrations and blood pressure. A randomized, crossover trial was used. Participants were healthy men and women (both n=15; age: 24±6 years) from the Netherlands. Participants were instructed to consume ∼400 mg nitrate at lunch, provided through nitrate-rich vegetables and dietary counseling, or beetroot juice supplementation. Both interventions lasted 1 week, with 1-week washout (January to April 2017). Plasma nitrate and nitrite concentrations and resting systolic and diastolic blood pressure were measured in an overnight fasted state (before and after intervention) and ∼2.5 hours after lunch (before and throughout intervention on day 1, 4, and 7). Two-factor (time × treatment) repeated-measures analyses of variance were performed. Mean plasma nitrate concentrations increased with both interventions, with a larger increase in beetroot juice vs nitrate-rich vegetables, both in a fasted state and ∼2.5 hours after lunch (day 1, beetroot juice: 2.31±0.56 mg/dL [373±90 μmol/L] vs nitrate-rich vegetables: 1.71±0.83 mg/dL [277±134 μmol/L]; P <0.001). Likewise, mean plasma nitrite concentrations increased with both interventions, but were higher after lunch in beetroot juice than in nitrate-rich vegetables (day 1: 2.58±1.52 μg/dL [560±331 nmol/L] vs 2.15±1.21 μg/dL [468±263 nmol/L]; P =0.020). Fasting mean systolic and diastolic blood pressure did not change, but mean systolic and diastolic blood pressure assessed ∼2.5 hours after lunch were significantly reduced throughout both intervention periods (P <0.05), with no differences between beetroot juice and nitrate-rich vegetables (day 1, systolic blood pressure: –5.1±9.5 mm Hg and diastolic blood pressure: –5.3±8.9 mm Hg). Short-term consumption of dietary nitrate in the form of nitrate-rich vegetables represents an effective means to increase plasma nitrate and nitrite concentrations, and reduces blood pressure to the same extent as beetroot juice supplementation.