Acute Effects of Nitrate-Rich Beetroot Juice on Blood Pressure, Hemostasis and Vascular Inflammation Markers in Healthy Older Adults: A Randomized, Placebo-Controlled Crossover Study

Nutrients. 2017 Nov 22;9(11):1270. doi: 10.3390/nu9111270.

Abstract

Aging is associated with a vasoconstrictive, pro-coagulant, and pro-inflammatory profile of arteries and a decline in the bioavailability of the endothelium-derived molecule nitric oxide. Dietary nitrate elicits vasodilatory, anti-coagulant and anti-inflammatory effects in younger individuals, but little is known about whether these benefits are evident in older adults. We investigated the effects of 140 mL of nitrate-rich (HI-NI; containing 12.9 mmol nitrate) versus nitrate-depleted beetroot juice (LO-NI; containing ≤0.04 mmol nitrate) on blood pressure, blood coagulation, vascular inflammation markers, plasma nitrate and nitrite before, and 3 h and 6 h after ingestion in healthy older adults (five males, seven females, mean age: 64 years, age range: 57-71 years) in a randomized, placebo-controlled, crossover study. Plasma nitrate and nitrite increased 3 and 6 h after HI-NI ingestion (p < 0.05). Systolic, diastolic and mean arterial blood pressure decreased 3 h relative to baseline after HI-NI ingestion only (p < 0.05). The number of blood monocyte-platelet aggregates decreased 3 h after HI-NI intake (p < 0.05), indicating reduced platelet activation. The number of blood CD11b-expressing granulocytes decreased 3 h following HI-NI beetroot juice intake (p < 0.05), suggesting a shift toward an anti-adhesive granulocyte phenotype. Numbers of blood CD14++CD16⁺ intermediate monocyte subtypes slightly increased 6 h after HI-NI beetroot juice ingestion (p < 0.05), but the clinical implications of this response are currently unclear. These findings provide new evidence for the acute effects of nitrate-rich beetroot juice on circulating immune cells and platelets. Further long-term research is warranted to determine if these effects reduce the risk of developing hypertension and vascular inflammation with aging.

Keywords: aging; anti-adhesive effects; anti-thrombotic effects; beetroot juice; blood pressure; dietary nitrate; low-grade inflammation; preserving vascular health; thrombosis.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Aging
  • Beta vulgaris / chemistry
  • Biomarkers / blood*
  • Blood Platelets / cytology
  • Blood Platelets / metabolism
  • Blood Pressure*
  • CD11b Antigen / metabolism
  • Cardiovascular Diseases / blood*
  • Cross-Over Studies
  • Diet
  • Double-Blind Method
  • Female
  • Fruit and Vegetable Juices*
  • Granulocytes / cytology
  • Hemostasis
  • Humans
  • Inflammation / blood*
  • Male
  • Middle Aged
  • Monocytes / cytology
  • Nitrates / administration & dosage*
  • Nitrates / blood
  • Nitrites / administration & dosage
  • Nitrites / blood
  • P-Selectin / blood
  • Plant Roots / chemistry
  • Prothrombin / metabolism
  • Thromboplastin / metabolism
  • Waist Circumference

Substances

  • Biomarkers
  • CD11b Antigen
  • ITGAM protein, human
  • Nitrates
  • Nitrites
  • P-Selectin
  • Prothrombin
  • Thromboplastin