Coffee consumption and risk of nonalcoholic fatty liver disease: a systematic review and meta-analysis.
OBJECTIVE
Nonalcoholic fatty liver disease (NAFLD) is a worldwide public health concern. Coffee might have a protective effect against NAFLD. However, the results of previous reports are conflicting. Therefore, we carried out this meta-analysis to summarize all available data.


METHODS
This study consisted of two meta-analyses. The first meta-analysis included observational studies comparing the risk of NAFLD in patients who did and did not drink coffee. The second analysis included studies comparing the risk of liver fibrosis between NAFLD patients who did and did not drink coffee. Pooled risk ratios (RR) and 95% confidence interval (CI) were calculated.


RESULTS
Out of 355 articles, five studies fulfilled our eligibility criteria and were included in the analysis. The risk of NAFLD in patients who drank coffee was significantly lower than that in patients who did not pooled RR 0.71 (95% CI, 0.60-0.85). We also found a significantly decreased risk of liver fibrosis among NAFLD patients who drank coffee compared with those who did not, with a pooled RR of 0.70 (95% CI, 0.60-0.82). However, it should be noted that the definition of regular coffee consumption varied between studies, which is the main limitation of this meta-analysis.


CONCLUSIONS
Our study found a significantly decreased risk of NAFLD among coffee drinkers and significantly decreased risk of liver fibrosis among patients with NAFLD who drank coffee on a regular basis. Whether consumption of coffee could be considered a preventative measure against NAFLD needs further investigations.
aDepartment of Internal Medicine, Bassett Medical Center, Cooperstown, New York bDepartment of Internal Medicine, Division of Rheumatology, Mayo Clinic, Rochester, Minnesota, USA cDepartment of Medicine, Division of Rheumatology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Karn
K
Wijarnpreecha
Charat
C
Thongprayoon
Patompong
P
Ungprasert
D003069:Coffee; D004327:Drinking Behavior; D006801:Humans; D008103:Liver Cirrhosis / Q000453:epidemiology*; D065626:Non-alcoholic Fatty Liver Disease / Q000453:epidemiology*; D016017:Odds Ratio; D065840:Protective Factors
D003069:Coffee