We can’t tell if belly fat leads to depression, depression leads to weight gain, or if both happen together — because this study only looked at people at one point in time.
Scientific Claim
The study’s cross-sectional design limits the ability to determine whether abdominal obesity causes psychiatric morbidity, increases risk over time, or is a consequence of mental health symptoms, leaving reverse causation and temporal ambiguity unresolved.
Original Statement
“Due to the cross-sectional study design, we could not define causality between the obesity-related indices and psychiatry morbidity. Further, more extensive longitudinal studies are warranted to clarify this issue. In addition, reverse causation remains possible, as psychiatric symptoms may influence weight patterns and fat distribution.”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The study correctly identifies its design limitation. The claim accurately reflects the authors’ own caution and aligns with GRADE Level 2b evidence standards.
Evidence from Studies
Supporting (1)
Abdominal Obesity Indices as Predictors of Psychiatric Morbidity in a Large-Scale Taiwanese Cohort
This study found that people with more belly fat also tended to have anxiety or depression, but because it only looked at them once, it can’t tell if the fat caused the mental health issues or if the mental health issues led to weight gain.