Background: The hypothesis of "cross-addiction" has never been validated, and numerous aspects speak against it., Objectives: To compare the differences between sleeve gastrectomy (SG) and gastric bypass (GB) procedures concerning cross-addiction., Setting: Center for maximum care in Germany., Methods: We performed a prospective analysis of patients undergoing SG or GB as the first surgical treatment for severe obesity. All patients completed validated questionnaires to evaluate food intake (Yale Food Addiction Scale, YFAS), alcohol intake (Alcohol Use Disorders Identification Test), nicotine use (Fagerstrom Test for Nicotine Dependence), exercise (Exercise Addiction Inventory), drug addiction (20-item Drug Abuse Screening Test), and Internet use disorder (Internet Addiction Test) before the operation (T0) and 6 (T6) and 24 (T24) months postoperatively (ClinicalTrials.gov identifier: NCT02757716)., Results: One hundred thirteen patients underwent SG (n = 68) or GB (n = 45). At the follow-up, 61% completed the questionnaires at T6 and 44% at T24. In the YFAS, the percentage of patients diagnosed with food addiction decreased from 69 to 10%, and the mean symptom count decreased from 3.52 ± 1.95 to 1.26 ± 0.99 at T24 (p < 0.0001); these values did not differ between the surgical groups (p = 0.784). No significant evidence of cross-addiction was observed for use of alcohol, nicotine, drugs, the Internet, or exercise in either surgical group. The percentage of patients with moderate nicotine dependence increased in the SG group (+8.9%) at T24, but this was not significant., Conclusion: In this single-center cohort study, surgery for obesity caused significant addiction remission regarding food but without inducing cross-addiction after 2 years. Importantly, no significant differences were seen between the SG and GB procedures., (© 2020 The Author(s) Published by S. Karger AG, Basel.)