Effects of cocoa consumption on cardiometabolic risk markers: Protocol for a systematic review and meta-analysis of randomized controlled trials

by Tainah Ortiz Pinto Arisi, Diego Silveira da Silva, Elana Stein, Camila Weschenfelder, Patrícia Caetano de Oliveira, Aline Marcadenti, Alexandre Machado Lehnen, Gustavo Waclawovsky

Background

Cardiometabolic diseases cover a spectrum of interrelated conditions linked to metabolic dysfunctions and/or cardiovascular disorders, including systemic arterial hypertension, diabetes mellitus, dyslipidemia, and obesity. Cocoa is a rich source of dietary polyphenols and has been associated with cardiovascular health benefits. However, beneficial effects of cocoa consumption and appropriate quantities in decreasing cardiometabolic risk factors have yet to be established. Therefore, we will conduct a systematic review and meta-analysis to examine the effects of cocoa consumption on cardiometabolic risk markers (total cholesterol, HDL, LDL, triglycerides, blood glucose, glycated hemoglobin, waist circumference, abdominal circumference, body mass index, systolic blood pressure and diastolic blood pressure) in adults with or without established cardiovascular risk factors.

Methods

Our review will include all randomized controlled trials published in English, Portuguese and Spanish with no date of publication restrictions evaluating the effects of cocoa consumption on cardiometabolic risk markers selected from the databases MEDLINE (PubMed), LILACS, Cochrane, EMBASE, Web of Science and SciELO, and gray literature. Eligible studies must involve adults (age ≥18y), and the consumption of cocoa or dark chocolate (≥ 70% cocoa), include a control group and evaluate blood pressure, anthropometric measurements, and lipid or glycemic profiles. We will use risk-of-bias 2 (RoB2) tool to assess the risk of bias and the GRADE system to assess the strength of evidence. Statistical analyses will be performed using RStudio for Windows and R package meta.

Discussion

This meta-analysis will summarize existing evidence on the effects of cocoa consumption on cardiometabolic health in adults. Better understanding the effects of cocoa consumption on anthropometric measurements, blood pressure, and lipid and glycemic profiles can provide valuable insights for health professionals to improve dietary recommendations regarding appropriate quantities.

Trial registration

Systematic Review Registration: PROSPERO CRD42023484490.