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Updated: May 11, 2026

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Published on: June 11, 2012
Pre-operative weight loss does not predict weight loss following laparoscopic adjustable gastric banding
Wendy A Brown1, Julia Moszkowicz, Leah Brennan
1Centre for Obesity Research and Education, Monash University, Level 6, 99 Commercial Road, Melbourne, 3004, Australia, Wendy.Brown@monash.edu.
Background:
This study aimed to test the hypothesis that the amount of weight lost on a mandatory 2-week pre-operative very-low-calorie diet (VLCD) would predict the longer-term outcomes of laparoscopic adjustable gastric banding (LAGB).
Methods:
All patients treated with a primary LAGB from 21 October 2008 until 30 June 2010, who were prescribed a 2-week pre-operative VLCD, have been included in the study. Patient age, weight, BMI and excess weight (defined as weight above a BMI of 25) were extracted on the day of first visit, day of surgery and at the post-operative visits at 3, 12 and 24 months. From these data, percent excess weight loss (EWL) was calculated and compared at all time points.
Results:
The weight loss achieved on a mandatory 2-week pre-operative diet did not predict weight outcomes at 2 years (r = -0.008; p = 0.931). Using multivariate analysis, the best predictor of 24-month percent EWL was percent EWL at 3 months post operation (sr(2) = 0.34; p = 0.003).
Conclusions:
Results from a pre-operative diet should not be used to predict the ultimate outcome of bariatric surgery. The weight loss at 3 months following LAGB was a strong predictor of longer-term outcomes. There may be potential for improving longer-term results with LAGB by better supporting patients who are not achieving good weight loss at this early time point.

