BACKGROUND: The BioEnterics Intragastric Balloon (BIB) has been considered an effective, less invasive method for weight loss, as it provides a permanent sensation of satiety. However, various non-randomized studies suggest BIB is a temporary anti-obesity treatment, which induces only a short-term weight loss. The purpose of this study was to present data of 500 obese who, after BIB-induced weight reduction, were followed up for up to 5 years.METHODS: The BioEnterics BIB was used, and remained for 6 months. At 6, 12, and 24 months post-removal (and yearly thereafter), all subjects were contacted for follow-up.RESULTS: From 500 patients enrolled, 26 were excluded (treatment protocol interruption); 474 thus remained, having initial body weight of 126.16 ± 28.32 kg, BMI of 43.73 ± 8.39 kg/m2, and excess weight (EW) of 61.35 ± 25.41. At time of removal, 79 (17%) were excluded as having percent excessive weight loss (EWL) of <20%; the remaining 395 had weight loss of 23.91 ± 9.08 kg (18.73%), BMI reduction of 8.34 ± 3.14 kg/m2 (18.82%), and percent EWL of 42.34 ± 19.07. At 6 and 12 months, 387 (98%) and 352 (89%) presented with weight loss of 24.14 ± 8.93 and 16.31 ± 7.41 kg, BMI reduction of 8.41 ± 3.10 and 5.67 ± 2.55 kg/m2, and percent EWL of 42.73 ± 18.87 and 27.71 ± 13.40, respectively. At 12 and 24 months, 187 (53%) and 96 (27%) of 352 continued to have percent EWL of >20. Finally, 195 of 474 who completed the 60-month follow-up presented weight loss of 7.26 ± 5.41 kg, BMI reduction of 2.53 ± 1.85 kg/m2, and percent EWL of 12.97 ± 8.54. At this time, 46 (23%) retained the percent EWL at >20. In general, those who lost 80% of the total weight lost during the first 3 months of treatment succeeded in maintaining a percent EWL of >20 long term after BIB removal: more precisely, this cutoff point was achieved in 83% at the time of removal and in 53%, 27%, and 23% at 12-, 24-, and 60-month follow-up.CONCLUSION: BIB seems to be effective for significant weight loss and maintenance for a long period thereafter, under the absolute prerequisite of patient compliance and behavior change from the very early stages of treatment.