61 - Beer and the Liver

Abstract

This chapter examines the evidence supporting the link between alcohol and liver disease. There is clear evidence that excessive alcohol consumption is associated with liver disease; this is true for all different types of alcoholic beverages. However, it is apparent that some beverages are more harmful, particularly spirits compared to wine or beer, although this is contentious. For example, the threshold value for the increases in serum gamma glutamyl transferase is higher with beer than alcohol in general. The interpretation of this is complicated by the evidence showing that alcoholics change their preference for a particular beverage type as liver disease progresses. Thus, in one study on cirrhotic patients, pre-alcoholics preferred beer as opposed to more ardent spirits in chronic alcoholics. There are other confounding issues. For example, there is a substantial body of evidence to support the notion that wine and beer drinkers have different diets. The importance of this relates to the observation that diet modulates the effect of alcohol. Thus, in patients with cirrhosis there is a positive correlation with beer consumption and ingestion of pork-related products. In contrast, there is a negative correlation between wine consumption and ingestion of pig products in patients with cirrhosis. There is also evidence that beer alters the biochemistry of the liver directly, for example modulating the response to ischemic stress and increasing enzymes involved in detoxification. However, light beers and dark beers have different effects on the liver. Unfortunately, this distinction between beer types has not been investigated in depth in clinical studies and this merits further investigation.