Effects of Caffeinated and Decaffeinated Coffee Consumption on Metabolic Syndrome Parameters: A Systematic Review and Meta-Analysis of Data from Randomised Controlled Trials

Ramli NNS, Alkhaldy AA, Mhd Jalil AM · Medicina · 2021 September 11

Objective

The systematic review and meta-analysis aim to investigate the effects of coffee consumption, particularly phenolic acids like caffeic acid and chlorogenic acid (CGA), on metabolic syndrome (MeTS) parameters.

Conclusions

The study concludes that green coffee extract (GCE) supplementation, specifically with doses containing 180 to 376 mg of CGA, reduces waist circumference, triglyceride levels, and blood pressure while increasing high-density lipoprotein-cholesterol levels. Decaffeinated coffee (510.6 mg) also showed a reduction in fasting blood glucose levels. The findings suggest that the impact of coffee on MeTS parameters varies depending on the types and doses administered, highlighting the need for more detailed randomized controlled trials (RCTs) to confirm these outcomes and explore specific coffee doses with adjustments for energy and polyphenol intake, as well as physical activity.

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Insights

Coffee extract supplementation significantly improves parameters of metabolic syndrome, with the effects varying according to the types and doses of coffee administered.

In this systematic review and meta-analysis, the researchers sourced relevant articles from PubMed and Scopus published between 2015 and 2020. The investigation focused on randomised controlled trials that studied the impact of coffee consumption on factors like body measurements, blood sugar indices, lipid profiles, and blood pressure. Effects of green coffee extract (GCE) supplementation and decaffeinated coffee were analysed in the study. Following a meticulous extraction and analysis of data from the relevant studies, the researchers found significant improvements in parameters of metabolic syndrome upon supplementation with GCE and decaffeinated coffee. The GCE supplementation, ranging from 180 to 376 mg, was found to reduce waist circumference, triglyceride levels, systolic and diastolic blood pressure while increasing high-density lipoprotein-cholesterol levels. The intake of decaffeinated coffee reduced fasting blood glucose levels. The analysis revealed improvements in metabolic syndrome outcomes for participants consuming GCE and liquid decaffeinated coffee.