Industrial, not fruit fructose intake is associated with the severity of liver fibrosis in genotype 1 chronic hepatitis C patients

摘要

To the Editor:In their study recently published in the Journal ofHepatology, Pet-ta et al. reported an independent association between advanced liver fibrosis in chronic hepatitis C virus (HCV) genotype 1 infection and 'industrial', but not fruit fructose intake [1 ]. While these findings are novel we believe this cross-sectional study has significant limitations that need to be addressed before the results can be applied to the broader HCV community.Firstly, the use of an American web-based calculator (www.health-diet.us/fructose) to quantify the fructose content of specific foods requires validation in an Italian population consuming locally produced and marketed food. The United States uses high fructose corn syrup as an additive sweetener to food and carbonated beverages to a much higher extent than many other countries. Hence the methodology used to calculate 'industrial' fructose intake may have resulted in significant bias being introduced into the study. The authors have not given any specific information of the use of high fructose corn syrup as a sweetener in Italy, but solely relied on extrapolation from American data and practices. Furthermore, the methodology of use of a three-day food diary is questionable when the progression of fibrosis in HCV infection occurs over years.Secondly, the very low"overall fructose intake by study participants (18.0 ± 8.7 g/day) limits the generalizability of the study. This low value is likely reflective of the regional dietary differences many Italians have when compared with other developed countries, including the United States of America. National dietary intake survey data shows that >95% of American residents consume <100g of fructose per day from all sources [2], while Australian adults consume <60 g total fructose per day [3]. These values are markedly higher than this study's population. Moreover, as those with advanced fibrosis only had 2.3 g higher mean intake of 'industrial' fructose per day than those without advanced fibrosis and the clinical relevance of such a small increase in this form of fructose is questionable.