Tart Cherry Concentrate Does Not Alter the Gut Microbiome, Glycaemic Control or Systemic Inflammation in a Middle-Aged Population

Nutrients. 2019 May 13;11(5):1063. doi: 10.3390/nu11051063.


Limited evidence suggests that the consumption of polyphenols may improve glycaemic control and insulin sensitivity. The gut microbiome produces phenolic metabolites and increases their bioavailability. A handful of studies have suggested that polyphenol consumption alters gut microbiome composition. There are no data available investigating such effects in polyphenol-rich Montmorency cherry (MC) supplementation. A total of 28 participants (aged 40-60 years) were randomized to receive daily MC or glucose and energy-matched placebo supplementation for 4 wk. Faecal and blood samples were obtained at baseline and at 4 wk. There was no clear effect of supplementation on glucose handling (Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) and Gutt indices), although the Matsuda index decreased significantly in the MC group post-supplementation, reflecting an increase in serum insulin concentration. Contrastingly, placebo, but not MC supplementation induced a 6% increase in the Oral Glucose Insulin Sensitivity (OGIS) estimate of glucose clearance. Serum IL-6 and C reactive protein were unaltered by either supplement. The faecal bacterial microbiome was sequenced; species richness and diversity were unchanged by MC or placebo and no significant correlation existed between changes in Bacteroides and Faecalibacterium abundance and any index of insulin sensitivity. Therefore, 4 weeks of MC supplementation did not alter the gut microbiome, glycaemic control or systemic concentrations of IL-6 and CRP in a middle-aged population.

Keywords: Montmorency; cherry; microbiome; polyphenol.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Biomarkers
  • Blood Glucose / drug effects*
  • C-Reactive Protein / genetics
  • C-Reactive Protein / metabolism
  • Dietary Supplements
  • Double-Blind Method
  • Feces / microbiology
  • Female
  • Gastrointestinal Microbiome / drug effects*
  • Gene Expression Regulation / drug effects
  • Glucose / administration & dosage
  • Glucose / metabolism
  • Humans
  • Inflammation / drug therapy*
  • Interleukin-6 / genetics
  • Interleukin-6 / metabolism
  • Male
  • Middle Aged
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Prunus avium / chemistry*


  • Biomarkers
  • Blood Glucose
  • Interleukin-6
  • Plant Extracts
  • C-Reactive Protein
  • Glucose