Objective: Patients' ability to judge health change over time has important clinical implications for treatment, but is understudied in longitudinal contexts with meaningful health change. We assess patients' awareness of health change for 5 years following bariatric surgery, and its association with weight loss. Method: Participants were part of the Longitudinal Assessment of Bariatric Surgery (N = 2,027). Perceived health change for each year was assessed by comparing it to self-reports of health on the SF-36 health survey. Participants were categorized as concordant when perceived and actual self-reported health change corresponded, and as discordant when they did not correspond. Results: Year-to-year concordance between perceived and actual self-reported health change occurred less than 50% of the time. Discordance between perceived and actual health was associated with weight loss following surgery. Discordant-positive participants who perceived their health change as more positive than was warranted lost more weight postsurgery and thus had lower body mass index scores than concordant participants. Conversely, discordantnegative participants who perceived their health as worse than what was warranted lost less weight post-surgery and thus had higher body mass index scores. Conclusions: These results suggest that recollection of past health is generally poor and can be biased by salient factors during recall. Clinicians are advised to use caution when retrospective judgments of health are utilized.