Effects of Montmorency Tart Cherry and Blueberry Juice on Cardiometabolic Outcomes in Healthy Individuals: Protocol for a 3-Arm Placebo Randomized Controlled Trial

Int J Environ Res Public Health. 2021 Sep 16;18(18):9759. doi: 10.3390/ijerph18189759.


Cardiometabolic disease is recognized as the predominant cause of global mortality and healthcare expenditure. Whilst pharmaceutical interventions are effective in the short term, their long-term efficacy remain equivocal and their associated side-effects are concerning. Owing to their high levels of anthocyanins, Montmorency tart cherries and blueberries have been cited as potentially important natural treatment/preventative modalities for cardiometabolic disease. This study proposed a randomized controlled trial, aims to test the effects of consumption of Montmorency tart cherry and blueberry juice on cardiometabolic outcomes compared to placebo. This 20-day, parallel, single-blind, randomized, placebo-controlled trial will recruit 45 individuals, who will be assigned to receive 60 mL per day of either Montmorency tart cherry juice, blueberry juice or a cherry/blueberry flavoured placebo. The primary study outcome is the between-group difference in systolic blood pressure from baseline to post-intervention. Secondary outcome measures will be between-group differences in anthropometric, energy expenditure and substrate oxidation (during rest and physical activity), haematological, blood pressure/resting heart rate, psychological wellbeing and sleep efficacy indices. Statistical analysis will be conducted on an intention-to-treat basis. This study has been granted ethical approval by the University of Central Lancashire, Health Research Ethics Committee (ref: HEALTH 0016) and formally registered as a trial. Dissemination of the study findings from this investigation will be through publication in a leading peer-reviewed journal.

Trial registration: ClinicalTrials.gov NCT04177238.

Keywords: blood pressure; blueberry; cardiovascular disease; metabolic health; tart cherry.

Publication types

  • Clinical Trial Protocol
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anthocyanins
  • Blueberry Plants*
  • Cardiovascular Diseases* / prevention & control
  • Humans
  • Prunus avium*
  • Randomized Controlled Trials as Topic
  • Single-Blind Method


  • Anthocyanins

Associated data

  • ClinicalTrials.gov/NCT04177238