Short Term Tea Consumption is not Associated with a Reduction in Blood Lipids or Pressure – A Systematic Review and Meta-Analysis of Randomized Controlled Trials: Tea and CVD Risk

Ebuwa Igho-Osagie, Kelly Cara, Deena Wang, Qisi Yao, Laura Penkert, Aedin Cassidy, Mario Ferruzzi, Paul Jacques, Elizabeth Johnson, Taylot Wallace*, Mei Chung

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)

Abstract

Background
A recent systematic review of epidemiological evidence suggests that higher amounts of tea intake are associated with lower risks of cardiovascular disease (CVD) incidence and mortality.

Objectives
Our study objective was to assess mechanisms by which tea consumption may influence CVD risks.

Methods
A systematic review and meta-analysis was conducted to investigate the effects of green and/or black tea consumption (≥4 wk) on systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol, LDL cholesterol, HDL cholesterol, and triglyceride (TG) in healthy populations and among at-risk adults (analyzed separately) with metabolic syndrome, prediabetes, and hypercholesterolemia. The Grading of Recommendations Assessment, Development and Evaluation approach was used to rate the strength of evidence (SoE).

Results
A total of 14 unique RCTs which randomly assigned 798 participants to either green tea, black tea, or placebo controls were included in our analyses. Intervention durations ranged from 4 to 24 wk (mean: 7.4 wk). Individual studies were judged as moderate to high quality based on risk of bias assessments. SoE was low to moderate owing to low sample sizes and insufficient power for most included studies to observe changes in the measured CVD biomarkers. Meta-analyses showed no significant effects of tea consumption on SBP, DBP, total cholesterol, LDL cholesterol, HDL cholesterol, and TG in healthy and at-risk adults (i.e., adults with obesity, prediabetes, borderline hypercholesterolemia, and metabolic syndrome).

Conclusions
Short-term (4–24 wk) tea consumption does not appear to significantly affect blood pressure or lipids in healthy or at-risk adults, although the evidence is limited by insufficient power to detect changes in these CVD biomarkers. High-quality RCTs with longer durations and sufficient sample sizes are needed to fully elucidate the effects of tea. This systematic review was registered at www.crd.york.ac.uk/prospero/ as CRD42020134513.
Original languageEnglish
Article numberJN-2020-0514R2
JournalThe Journal of Nutrition
Early online date13 Nov 2020
DOIs
Publication statusEarly online date - 13 Nov 2020

Keywords

  • Camellia sinensis, tea, blood pressure, lipids, cardiovascular diseases

Fingerprint Dive into the research topics of 'Short Term Tea Consumption is not Associated with a Reduction in Blood Lipids or Pressure – A Systematic Review and Meta-Analysis of Randomized Controlled Trials: Tea and CVD Risk'. Together they form a unique fingerprint.

Cite this