Hostname: page-component-6b989bf9dc-476zt Total loading time: 0 Render date: 2024-04-14T17:53:38.116Z Has data issue: false hasContentIssue false

Tea Flavonoids and Risk of Cardiovascular and All-Cause Mortality: A Systematic Review and Meta-Analysis

Published online by Cambridge University Press:  10 June 2020

Ding Ding Wang
Affiliation:
D&V Systematic Reviewe, LLC, Bronx, NY, USA
Aedin Cassidy
Affiliation:
The University of East Anglia, Norfolk, USA
Mario G. Ferruzzi
Affiliation:
North Carolina State University, Kannapolis, NC, USA
Paul Jacques
Affiliation:
Tufts University, Boston, MA, USA
Elizabeth Johnson
Affiliation:
Tufts University, Boston, MA, USA
Naisi Zhao
Affiliation:
Tufts University, Boston, MA, USA
Marissa Shams-White
Affiliation:
Tufts University, Boston, MA, USA
Micaela Karlsen
Affiliation:
Tufts University, Boston, MA, USA
Taylor C. Wallace
Affiliation:
Think Healthy Group, Inc., Washington, DC, USA George Mason University, Fairfax, VA, USA
Mei Chung
Affiliation:
Tufts University, Boston, MA, USA
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

There is increasing evidence that both black and green tea are beneficial for prevention of cardiovascular disease (CVD). We conducted a systematic review and meta-analysis evaluating the effects of tea flavonoids on cardiovascular (CVD) and all-cause mortality outcomes.Searches across five databases including PubMed and Embase were conducted through November 2018 to identify randomized controlled trials (RCTs) and prospective cohort studies reporting cardiovascular and all-cause mortality outcomes. Two investigators independently conducted abstract and full-text screenings, data extractions, and risk of bias (ROB) assessments using the Nutrition Evidence Library Bias Assessment Tool (NEL BAT). Mixed-effects dose-response meta-regression and standard random-effects meta-analyses for outcomes with ≥ 4 studies were performed. 0 RCTs and 38 prospective cohort studies were included in the systematic review. NEL BAT scores ranged from 0–15 (0 being the lowest risk). Our linear meta-regression model showed that each cup increase in daily tea consumption (about 280 mg and 338 mg of total flavonoids for black and green tea, respectively) was associated with 3–4% lower risk of CVD mortality (predicted adjusted RR = 0.96; CI 0.93–0.99 for green tea and RR = 0.97; CI 0.94–0.99 for black tea). Furthermore, eachcup increase in daily tea consumption was associated a 2% lower risk of all-cause mortality (predicted adjusted relative risk (RR) = 0.98; 95% CI 0.97–0.99 for black tea and RR = 0.98; CI 0.96–0.99 for green tea, respectively). Two studies reported multivariable Cox regression analysis results for the relationship between black tea intake and risks of all-cause mortality outcomes. The results from these two studies were combined with our linear meta-regression result in a random-effects model meta-analysis and showed that each cup increase in daily black tea consumption was associated with an average of 3% lower risk of all-cause mortality (pooled adjusted RR = 0.97; 95% CI 0.87- 1.00) with large heterogeneity (I2 = 81.4%; p = 0.005). Current evidence indicates that increased tea consumption may reduce cardiovascular and all-cause mortality in a dose-response manner. This systematic review was registered on PROSPERO.

Type
Abstract
Copyright
Copyright © The Authors 2020