 Materials and Methods: We included 28 females 12 gastric bypass patients, 8 obese and 8 normal weight subjects in the study. Each participant had to drink 250 ml white wine. Directly before, 10-30 min after and 45-65 min after wine consumption cognitive functions were tested by test battery for attentional performance TAP from Zimmermann and Fimm. During the whole examination breath-alcohol-contents BACs were measured every 5 minutes with breathalyser Dräger Alcotest 7510. 