Background: There have been numerous inconsistencies in the results of studies exploring the association of BMI and depression. This can be attributed to unaccounted confounding variables in the psychosocial aspect, such as weight perception. The aim of this study was to determine if weight perception is more strongly associated with clinically relevant depression than directly measured BMI. Due to the dearth of studies, this study also explored the patterns of the associations across sex, age, and race/ethnicity.
Study Population and Methods: This study conducted a cross-sectional study using data on adults aged 18 and above from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2016 (N= 10,068). Multiple logistic regression analyses were performed to evaluate the association of actual BMI status (calculated from measured height and weight), weight perception and weight misperception patterns to depression (Patient Health Questionnaire-9, ≥ 10 score) while adjusting for potential covariates. Further analyses were done to examine the different patterns of the associations across sex, age and race/ethnicities.
Results: This study has found the weight perception was indeed more strongly associated with depression as compared to directly measured BMI. Results show that obese men (OR=0.70, 95% CI:0.50-0.97), overweight women (OR=0.74, 95% CI:0.56-0.98) and overweight adults aged 18-39 (OR=0.56, 95% CI:0.40-0.79) seemed to have lower odds of depression compared to adults with normal BMI. On the other hand, underweight and/or overweight perception increased depression odds in both sexes, in middle-aged and older adults and in Mexican Americans, Whites, and Blacks. Weight misperception also increased the risk of being depressed in Blacks when they overestimate and Asians when they underestimate their weight. Lastly, other ethnicities, including multiracial persons, are less likely to be depressed when they underestimate their weight.
Conclusion: Overweight and underweight perceptions, rather than BMI, are more strongly associated with depression. Adults who view themselves as deviating from the societal ideal of normal body size and weight are more at risk of depression and this pattern is somehow consistent across sex, age groups, and race/ethnicities.
