Beer affects oxidative stress due to ethanol: A preclinical and clinical study

The oxidation of ethanol (ETOH) and its metabolites increase the production of superoxide anion and hydrogen peroxide, leading to initiation of peroxidation. The sensitivity to peroxidation is due to the overall balance between prooxidants and antioxidants. On the other hand, an increase of the antioxidant activity in blood of subjects with a moderate alcohol intake has been recently indicated as a possible protective mechanism. Beer has many non-alcoholic components with antioxidant properties such as vitamins, minerals, organic and inorganic salts, and phenolic compounds. The present chapter summarizes the results obtained by our laboratory on the effects of different alcoholic beverages, including beer, in both animals and humans. In particular, both preclinical and clinical studies showed that ETOH per se seems to decrease antioxidant parameters and increase lipoperoxidation. However, some of these changes appear to be attenuated when ETOH is consumed in beer. This aspect could be related to the counteracting effects of other antioxidant components.