Associations Between Changes in Activity and Dietary Behaviors after Metabolic and Bariatric Surgery.

Introduction: Patients who undergo metabolic and bariatric surgery (MBS) are advised to make healthy activity and dietary changes. While previous research has examined post-surgical changes in activity and dietary behaviors separately, no study has assessed whether changes in these behaviors are beneficially associated with each other. We evaluated whether post-surgical improvements in activity behaviors related to favorable changes in dietary behaviors overall and by surgery type (Roux-en-Y gastric bypass [RYGB], sleeve gastrectomy [SG]).

Methods: At pre-surgery and 6- and 12-months post-surgery, participants (N = 97; 67 RYGB/30 SG) wore an accelerometer for 7 days and completed 24-h dietary assessments on 3 days. General linear models assessed associations between pre- to post-surgical changes in activity (moderate-to-vigorous physical intensity activity [MVPA], sedentary time [ST]) and dietary (total energy intake [EI; kcal/day], dietary quality [healthy eating index/HEI scores]) behaviors, with surgery type as a moderator.

Results: Participants on average: demonstrated small, non-significant post-surgical changes in MVPA and ST minutes/day (ps > .05); and reported significant post-surgical decreases in EI (p < .001), but no changes in HEI scores (ps > .25). Greater 12-month post-surgical increases in MVPA were significantly associated with greater decreases in EI, but only for RYGB participants (p < .001).

Discussion: Participants reported large decreases in EI, but made minimal changes in other behaviors after MBS. Results suggest greater increases in MVPA could assist with achieving greater decreases in EI, although this benefit appears to be limited to RYGB patients. Additional research is needed to confirm these findings and determine whether activity-dietary behavior associations differ beyond the immediate post-surgical year.