Medscape Gastroenterology > Viewpoint > Coffee Consumption and Chronic Liver Disease: The New Best Prescription?
David A. Johnson, MD Disclosures January 06, 2014
Review Article: Coffee Consumption, the Metabolic Syndrome and Non-alcoholic Fatty Liver Disease Yesil A, Yilmaz Y
Aliment Pharmacol Ther. 2013;38:1038-1044 Study Summary

Coffee consumption is a part of daily life in most areas of the world. As such, a number of studies have evaluated the chemical composition and related effects that this enjoyable beverage may have on health and disease.

Yesil and Yilmaz analyzed the experimental, epidemiologic, and clinical studies and the modulation of the metabolic syndrome and nonalcoholic fatty liver disease (NAFLD). Animal studies showed a reduction in the metabolic syndrome with improvements in glycemic and lipid regulation, as well as reductions in transaminases and proinflammatory cytokine hepatic gene expression. Other studies showed reductions in hepatic fat and collagen proinflammatory tumor necrosis factor, as well as increases in anti-inflammatory interleukins. Epidemiologic and clinical studies demonstrated a significant inverse association between coffee consumption and prevalence of metabolic syndrome, as well as a reduced risk for NAFLD.

Abstract Coffee Reduces Risk for Hepatocellular Carcinoma: An Updated Meta-analysis Bravi F, Bosetti C, Tavani A, Gallus S, La Vecchia C
Clin Gastroenterol Hepatol. 2013;11:1413-1421

Study Summary

The meta-analysis by Bravi and colleagues is a logical extension of the data demonstrating the beneficial effects of coffee on NAFLD, now showing a reduction in associated risk for hepatocellular carcinoma (HCC). Sixteen studies were identified. Overall, compared with no coffee consumption, the risk for HCC was reduced by 28% with low-level consumption, and by 36% with high-level consumption (3 or more cups/day). It is likely that this favorable effect is the result of reduced cirrhosis evident in coffee drinkers, as well as improvement in the metabolic syndrome, because diabetes is another known risk factor for HCC. The researchers adjusted for other major risk factors for HCC, including hepatitis B virus, hepatitis C virus, cirrhosis, alcohol use, and tobacco use.

The data on beneficial effects of coffee consumption are impressive. These effects extend across all geographic areas as well as evidence from animals and retrospective and prospective clinical studies.

There are differences in coffee bean composition as well as extractions used in preparation, but these findings seem to be specifically related to brewed, roasted, regular (not decaffeinated) coffee. Of interest, the beneficial effects have not been evident in nonfiltered, boiled (Turkish), or French press preparations.Reportedly, there are more than 1500 chemical components of coffee, which are subject to agricultural and preparation-related influences. Although caffeine is the major active ingredient, many other components have significant antioxidant activity. Caffeine was thought previously to have antioxidant effects, but this has not been demonstrated subsequently in animal or human models.

The specific mechanisms by which coffee exerts these beneficial effects have not been clearly defined. What is apparent is that these effects extend across the spectrum of liver disease, ranging from hepatic steatosis to fibrosis, cirrhosis, and HCC. Of interest, these beneficial effects do not seem to extend to risk reduction for pancreatic cancer. [1] On the basis of the evidence, however, moderate consumption of brewed regular coffee seems to have clinical benefit for patients at risk for NAFLD or viral-related hepatic fibrosis. As clinicians who often recommend avoidance or reduction of delectables that contribute to disease states, it is nice to be able to give one back to patients.