Acute Supplementation with Nitrate-Rich Beetroot Juice Causes a Greater Increase in Plasma Nitrite and Reduction in Blood Pressure of Older Compared to Younger Adults

Abstract

Nitrate-rich beetroot juice supplementation has been shown to improve cardiovascular and cognitive function in younger and older adults via increased nitric oxide production. However, it is unclear whether the level of effects differs between the two groups. We hypothesized that acute supplementation with nitrate-rich beetroot juice would improve cardiovascular and cognitive function in older and younger adults, with the potential for greater improvements in older adults. Thirteen younger (18–30 years) and 11 older (50–70 years) adults consumed either 150 mL of nitrate-rich beetroot juice (BR; 10.5 mmol nitrate) or placebo (PL; 1 mmol nitrate) in a double-blind, crossover design, 2.25 h prior to a 30-min treadmill walk. Plasma nitrate and nitrite concentrations, blood pressure (BP), heart rate (HR), cognitive function, mood and perceptual tests were performed throughout the trial. BR consumption significantly increased plasma nitrate (p < 0.001) and nitrite (p = 0.003) concentrations and reduced systolic BP (p < 0.001) in both age groups and reduced diastolic BP (p = 0.013) in older adults. Older adults showed a greater elevation in plasma nitrite (p = 0.038) and a greater reduction in diastolic BP (p = 0.005) following BR consumption than younger adults. Reaction time was improved in the Stroop test following BR supplementation for both groups (p = 0.045). Acute BR supplementation increased plasma nitrite concentrations and reduced diastolic BP to a greater degree in older adults; whilst systolic BP was reduced in both older and younger adults, suggesting nitrate-rich BR may improve cardiovascular health, particularly in older adults due to the greater benefits from reductions in diastolic BP.

Beetroot as a Potential Functional Food for Cancer Chemoprevention, a Narrative Review

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Beetroot supplementation in women enjoying exercise together (BEE SWEET): Rationale, design and methods

“…From a mechanistic perspective, we reason that the additive effects of nitric oxide - derived through chronic beetroot juice ingestion and repetitive shear stress invoked during resistance exercise training sessions (3 times per week for 8 weeks) [ 70 ] - will result in more robust endothelium-dependent vascular adaptations when compared to exercise training alone. Separately, dietary nitrate and habitual exercise training interventions have favorably influenced blood pressure [ 19 , [71] , [72] , [73] ], macrovascular [ 7 , 73 , 74 ], and microvascular function [ 75 ] in healthy older men and women. However, the cumulative effect of dietary nitrate coupled with exercise training has not yet been compared to exercise training alone, and it is further unknown whether such interventions will elicit differing adaptations in conduit or resistance vessels [ 63 , 73 ].…”

Dietary nitrate supplementation increases diaphragm peak power in old mice

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