Reply to: “Regular coffee: A magic bullet or a naked gun? Regular coffee but not espresso drinking is protective against fibrosis in NAFLD”
Authors: Rodolphe Anty, Sophie Marjoux, Antonio Iannelli, Alexandre Pariente, Albert Tran
Journal: Journal of Hepatology (2013)

Regular coffee but not espresso drinking is protective against fibrosis in a cohort mainly composed of morbidly obese European women with NAFLD undergoing bariatric surgeryJournal of HepatologyVol. 57Issue 5PreviewThe aim of this study was to determine the influence of coffee and other caffeinated drinks on liver fibrosis of severely obese European patients. Full-Text PDF Regular coffee: A magic bullet or a naked gun? Regular coffee but not espresso drinking is protective against fibrosis in NAFLDJournal of HepatologyVol. 58Issue 6PreviewWe read with interest the article by Anty et al. [1] reporting that consumption of regular coffee but not of espresso is an independent protective factor for liver fibrosis, in severely obese European patients. Effects of coffee and caffeine on liver disease, including NAFLD, cirrhosis and HCC, have been reported over several years, with different methodological approaches and non-univocal results [2–4]. We appreciate the great effort that the authors have put, working with an extremely selected population, and using very careful tools for the assessment of steatosis and fibrosis. Full-Text PDF Open Access We have read with interest the comments and criticisms made by Trovato and colleagues concerning our recently published study [[1]Anty R. Marjoux S. Iannelli A. Patouraux S. Schneck A.S. Bonnafous S. et al.Regular coffee but not espresso drinking is protective against fibrosis in a cohort mainly composed of morbidly obese European women with NAFLD undergoing bariatric surgery.J Hepatol. 2012; 57: 1090-1096Abstract Full Text Full Text PDF PubMed Scopus (114) Google Scholar]. We would like to clarify a number of specific points. Firstly, we agree that our study population – morbidly obese patients referred for bariatric surgery – is a very particular group; morbidly obese subjects represent one percent of the French population. Our patients were consecutively enrolled in the bariatric program and agreed to complete a detailed questionnaire, given by a trained interviewer, assessing their coffee and caffeinated drink consumption. For each patient, a liver biopsy was obtained and assessed by validated classification. This histological analysis remains the gold standard to determine the various elementary lesions of NAFLD and NASH. This method is reliable and allowed us to differentiate pure steatosis, NASH, and the various degrees of fibrosis, in contrast to the use of only non-invasive methods such as liver ultrasound, as in the study by Catalano et al. [[2]Catalano D. Martines G.F. Tonzuso A. Pirri C. Trovato F.M. Trovato G.M. Protective role of coffee in non-alcoholic fatty liver disease (NAFLD).Dig Dis Sci. 2010; 55: 3200-3206Crossref PubMed Scopus (83) Google Scholar]. Secondly, as we stated in the Discussion, we do not know why the consumption of filtered regular coffee and not the consumption of espresso was associated with less fibrosis, in our cohort of morbidly obese patients. An initial hypothesis is that these two high-quality beverages are different in their composition because of their specific manufacturing processes. Another hypothesis is that regular and espresso drinkers have hidden, intrinsic differences. For example, espresso drinkers could use a higher quantity of sugar or use special forms of sugar (enriched in fructose for example). In our study, we found a positive correlation between the consumption of espresso and the number of parameters of the metabolic syndrome, the level of triglycerides, and a negative correlation with the level of HDL cholesterol. We must keep in mind that if 6 g of sugar (the usual amount of sugar served with an espresso in France) is added to an espresso of 50 ml, the concentration of sugar (120 g/L) is slightly higher than a typical cola-based soft drink (35 g of sugar for 330 ml, i.e., 106 g/L). As we stated in the Discussion, we did not take into account the amount and type of sugar added to coffee in the questionnaire, and the last sentence of our paper was intended as a joke! Studies including more detail concerning consumption should answer this question, as was done in the Nutrinet study in France [[3]Nutrinet. <https://www.etude-nutrinet-sante.fr/fr/common/login.aspx>.Google Scholar]. Our study probably reflects the current mode of consumption of coffee in France. The espresso drunk by our patients is essentially home-made using small machines, which are becoming more and more popular. The obtained beverages are different from the filtered coffee and possibly from the espresso made in coffee shops [[4]Aubin H.J. Berlin I. Coffee drinking and mortality.N Engl J Med. 2012; 367 (author reply 576–577): 576PubMed Google Scholar]. The volume obtained with these machines can vary from “ristretto” (25 ml), standard “espresso” (40 ml) to “lungo” (110 ml). Moreover, in the case of the “espresso” made by professionals, the quality of the obtained beverage can be very different, depending on the coffee shop, in terms of caffeine, chlorogenic acid and probably in the content of other compounds [[5]Crozier T.W. Stalmach A. Lean M.E. Crozier A. Espresso coffees, caffeine and chlorogenic acid intake: potential health implications.Food Funct. 2012; 3: 30-33Crossref PubMed Scopus (133) Google Scholar]. So the term “espresso” designates different beverages, and the delicious “ristretto espresso” made in a traditional Italian coffee shop is probably different from the beverage currently obtained at home in France with a small coffee machine. Thirdly, a questionnaire is an imperfect way of collecting information but has been used extensively and validated in epidemiological studies on coffee that include cohort studies [[5]Crozier T.W. Stalmach A. Lean M.E. Crozier A. Espresso coffees, caffeine and chlorogenic acid intake: potential health implications.Food Funct. 2012; 3: 30-33Crossref PubMed Scopus (133) Google Scholar]. With respect to our patients, it appeared that the daily consumption of coffee was regular over time and generally well recalled. The multivariate analysis has been performed using standard statistics. For logistic regression, non-redundant parameters that are significant in univariate analysis were selected. The quantity of regular coffee consumed and the approximate amount of caffeine from regular coffee were the same variable expressed in a different way. The patients were asked the volume of the various kinds of coffee and other caffeinated drinks consumed. A conversion table automatically converted the amount of each drink into the amount of caffeine consumed. This is why only the equivalence in caffeine consumption was finally retained for multivariate analysis. Similarly, AST and ALT were linked together. We chose AST because it is also a marker of fibrosis. In a model including AST and ALT, we obtained a similar result for regular coffee consumption (OR = 0.76, 95% CI: 0.58–0.99, p= 0.041). Fourthly, we recognize that we did not provide a complete nutritional and lifestyle assessment in our study. However, known confounders for coffee association, alcohol and tobacco use, were assessed and were similar in patients with and without significant fibrosis. Finally, our study is in accordance with the recent results of Molloy et al. who found a beneficial effect of filtered coffee consumption on the level of fibrosis of morbidly obese American patients [[6]Molloy J.W. Calcagno C.J. Williams C.D. Jones F.J. Torres D.M. Harrison S.A. Association of coffee and caffeine consumption with fatty liver disease, nonalcoholic steatohepatitis, and degree of hepatic fibrosis.Hepatology. 2011; 10: 24731Google Scholar]. As observed in our study, no effect was seen on the degree of NASH. Bambha et al. also observed a beneficial effect of regular coffee consumption on liver fibrosis in NAFLD patients, however, only in patients with a low level of insulin resistance [[7]Bambha K. Wilson L. Unalp A. Loomba R. Neuschwander-Tetri B.A. Brunt E.M. et al.Coffee consumption in NAFLD patients with lower insulin resistance is associated with lower risk of severe fibrosis.Hepatology. 2012; 56: 242ACrossref Google Scholar]. The positive effect of filtered coffee on overall mortality and on liver morbidity has also been demonstrated in a large number of studies. Due to the changing ways of consuming coffee, new epidemiological studies are necessary to better analyze the relationships between coffee consumption and liver diseases. Translational studies have to be performed to find the mechanisms and substance(s) of potential pharmacological interest. We can wait (calmly) for these results while drinking some (mainly regular?) coffee, probably without adding a sweetener and certainly without smoking cigarettes! The authors declared that they do not have anything to disclose regarding funding or conflict of interest with respect to this manuscript.