Oral Presentation ESA-SRB-ANZOS 2025 in conjunction with ENSA

Long-term effects of bariatric surgery on lifestyle behaviours (127745)

Michael Do 1 , Jacqueline R Center 2 3 , Malgorzata M Brzozowska 2 4 5
  1. Campbelltown Hospital, Campbelltown, NSW, Australia
  2. Garvan institute of Medical Research, Darlinghurst, NSW, Australia
  3. Department of Endocrinology, St Vincent's Hospital, Darlinghurst, NSW, Australia
  4. Department of Endocrinology, Sutherland Hospital, Caringbah, NSW, Australia
  5. UNSW Sydney, Sydney, NSW, Australia

Obesity carries significant health risks. Although bariatric surgery is an effective treatment for severe obesity, its long-term effects on diet, appetite and physical activity remain unclear[1-3].

This prospective study followed 57 adults over 36 months following Roux-en-Y gastric bypass (RYGB, n=7), sleeve gastrectomy (SG, n=21), laparoscopic adjustable gastric banding (LAGB, n=11) and dietary intervention (Diet, n=18). Dietary intake was recorded using 3-day food diaries, appetite measured via visual analogue scales and physical activity quantified by validated questionnaires covering light (<3.0 METs), moderate (3.0–6.0 METs), and vigorous (>6.0 METs) exercise. Within-group changes were analysed using Wilcoxon signed-rank tests.

At 36 months, SG and RYGB groups showed sustained weight loss (-30.6 kg and -28.5 kg, p<0.02), respectively, whereas LAGB induced early weight loss (-12.6 kg at 6 months, p<0.01) followed by partial regain. Diet lost weight initially (-2.7 kg at 12 months, p<0.01) returning to baseline by 24 months.

Energy intake decreased sharply after surgery in SG (-68%) and RYGB (-64%) at 1 month (p<0.01), with sustained reductions (36-40%) at 36 months. However, fat intake declined significantly in SG (35% to 28%) and RYGB (34.5% to 25.0%), while protein intake increased in both (up to 25.5% and 32.0%, respectively) for 3 months only, with no sustained difference after 12 months. RYGB showed reduced carbohydrate intake and increased calcium intake (up to 1428.0 mg) at 3 years. LAGB did not change macronutrient intake beyond 12 months.

Physical activity increased significantly in RYGB (light: +165min/day; moderate: +112.5min/day at 36 months) and up to 24 months in SG. Appetite suppression persisted up to 24 months after RYGB and 36 months after SG (p<0.01).

SG and RYGB improved weight, intake, and appetite, with RYGB showing the greatest physical activity gain. LAGB showed less durable effects, highlighting the need for ongoing nutritional and behavioural support.

  1. Behary P, Miras AD. Food preferences and underlying mechanisms after bariatric surgery. Proceedings of the Nutrition Society. 2015;74(4):419-425. doi:10.1017/S0029665115002074
  2. Ren Z, Lu G, Zhang T, et al. Effect of physical exercise on weight loss and physical function following bariatric surgery: a meta-analysis of randomised controlled trials. BMJ Open 2018;8:e023208. doi: 10.1136/bmjopen-2018-023208
  3. Adil MT, Jain V, Rashid F, Al-Taan O, Al-Rashedy M, Jambulingam P, Whitelaw D. Meta-analysis of the effect of bariatric surgery on physical activity. Surgery for obesity and related diseases. 2019 Sep 1;15(9):1620-31.