Coffee and metabolic syndrome: A systematic review and meta-analysis / 한국영양학회지

ABSTRACT

PURPOSE: Coffee is the most frequently consumed food item in South Korea after rice and cabbage. Coffee contains various substances, including caffeine, cafestol, kahweol, chlorogenic acid, and many other known and unknown ingredients with some health benefits. Especially, cumulative evidence has shown that regular coffee use is associated with lower risk of type 2 diabetes, although limited and inconsistent data are available regarding metabolic syndrome. METHODS: This study reviewed all available scientific and epidemiologic evidence on coffee consumption, metabolic syndrome, and the association between them. Most epidemiologic research regarding this association was of a cross-sectional design, and a few case-control and cohort studies were available. We conducted meta-analysis with 11 observational studies investigated in Europe, America, and Asia. Summary odds ratios (OR) were calculated using a random-effects model. RESULTS: The overall OR of metabolic syndrome was 0.90 (95% Confidence Interval (CI), 0.81-0.99) for the highest category of coffee intake compared with the lowest intake category. These associations were stronger in populations of US and Europe (OR 0.84, 95% CI 0.76-0.94), whereas no association was observed in the Asian population (OR 1.00, 95% CI 0.81-1.23). CONCLUSION: The review results indicate that frequent coffee consumption may be beneficial to metabolic syndrome, but the association between coffee consumption and metabolic syndrome may differ by nations or continents.