There has recently been a lot of attention in the media
around links between coffee and liver health. Markus Peck-Radosavljevic,
Secretary General at the European Association for the Study of the Liver, provides an overview of research on coffee and the liver.
Even though initial reports on the beneficial effect of coffee consumption on liver enzymes appeared around 20 years ago1, it was not until 2005 that this association was coming under closer scrutiny by clinical as well as basic researchers alike2-4.
Since then, the topic has attracted considerable interest. Coffee
consumption has repeatedly been shown to be associated with the
reduction of liver enzyme levels, incidence of chronic liver disease,
risk of liver cancer (HCC), disease progression in chronic hepatitis C5, reduction in liver fibrosis6, response to antiviral therapy in hepatitis C7, and the development of fatty liver and non-alcoholic steatohepatitis (NASH)8.
Despite considerable efforts, no conclusive evidence about the active
ingredient in coffee let alone the exact mechanism of action of coffee
on liver disease progression can be elucidated to date. But with coffee
consisting of over 1,000 different compounds and the lack of
standardization in the coffee preparation used in the cohorts studied,
this does not come as a big surprise.
Most recently the focus has mainly been on the effect of coffee on
the progression of NAFLD (non-alcoholic fatty liver disease) as well as
the development of liver cancer. A large Finnish study, including over
60,000 individuals across a 19 year follow-up period, was able to show a
dose-dependent decrease of the rate of HCC-development in the
consumption of up to 6 cups of coffee per day9. This year’s
meta-analysis of the impact of coffee consumption on the risk of
HCC-development was able to confirm this association10.
Likewise, a meta-analytic review of the evidence for preventing
development and progression of NAFLD by coffee consumption was able to
substantiate the protective effect of coffee on NAFLD in the
experimental as well as the clinical setting11. Taking the
current evidence together, we still don’t have definitive proof of the
protective effect of coffee from prospective trials and detailed
mechanistic insight into how this could be facilitated. Nevertheless,
considering the risks involved, it seems sensible to think about
recommending coffee for prevention of liver disease in individuals at
risk.
References:
1Casiglia E, Spolaore P, Ginocchio G, Ambrosio GB.
Unexpected effects of coffee consumption on liver enzymes. Eur J
Epidemiol 1993;9:293-297.
2Ruhl CE, Everhart JE. Coffee and tea consumption are
associated with a lower incidence of chronic liver disease in the United
States. Gastroenterology 2005;129:1928-1936.
3La Vecchia C. Coffee, liver enzymes, cirrhosis and liver cancer. J Hepatol 2005;42:444-446.
4Gelatti U, Covolo L, Franceschini M, Pirali F, Tagger A,
Ribero ML, Trevisi P, Martelli C, Nardi G, Donato F. Coffee consumption
reduces the risk of hepatocellular carcinoma independently of its
aetiology: a case-control study. J Hepatol 2005;42:528-534.
5Freedman ND, Everhart JE, Lindsay KL, Ghany MG, Curto TM,
Shiffman ML, Lee WM, Lok AS, Di Bisceglie AM, Bonkovsky HL, Hoefs JC,
Dienstag JL, Morishima C, Abnet CC, Sinha R. Coffee intake is associated
with lower rates of liver disease progression in chronic hepatitis C.
Hepatology 2009;50:1360-1369.
6Modi AA, Feld JJ, Park Y, Kleiner DE, Everhart JE, Liang
TJ, Hoofnagle JH. Increased caffeine consumption is associated with
reduced hepatic fibrosis. Hepatology 2010;51:201-209.
7Freedman ND, Curto TM, Lindsay KL, Wright EC, Sinha R,
Everhart JE. Coffee consumption is associated with response to
peginterferon and ribavirin therapy in patients with chronic hepatitis
C. Gastroenterology 2011;140:1961-1969.
8Molloy JW, Calcagno CJ, Williams CD, Jones FJ, Torres DM,
Harrison SA. Association of coffee and caffeine consumption with fatty
liver disease, nonalcoholic steatohepatitis, and degree of hepatic
fibrosis. Hepatology 2012;55:429-436.
9Hu G, Tuomilehto J, Pukkala E, Hakulinen T, Antikainen R,
Vartiainen E, Jousilahti P. Joint effects of coffee consumption and
serum gamma-glutamyltransferase on the risk of liver cancer. Hepatology
2008;48:129-136.
10Sang LX, Chang B, Li XH, Jiang M. Consumption of coffee
associated with reduced risk of liver cancer: a meta-analysis. BMC
Gastroenterol 2013;13:34.
11Yesil A, Yilmaz Y. Review article: coffee consumption,
the metabolic syndrome and non-alcoholic fatty liver disease. Aliment
Pharmacol Ther 2013;38:1038-1044.
Source:
Coffee and Health