Protective Misperception? Prospective Study of Weight Self-Perception and Blood Pressure in Adolescents With Overweight and Obesity

Abstract

Purpose Underestimating one’s weight is often seen as a barrier to weight loss. However, recent research has shown that weight under-perception may be beneficial, with lower future weight gain and fewer depressive symptoms. Here, we examine the relationship between adolescent weight under-perception and future blood pressure. Methods Using data from the National Longitudinal Study of Adolescent to Adult Health, we obtained a nationally representative sample of 2463 adolescents with overweight and obesity (students in grades 8–12 in 1996). We used multivariable linear regression to prospectively examine the relationship between weight self-perception in adolescence and blood pressure in adulthood (year 2008; follow-up rate 80.3%), controlling for age, gender, race/ethnicity, smoking, alcohol consumption, education level, household income, and BMI. Additional analyses were stratified by gender and race/ethnicity. Results Youth with overweight/obesity who under-perceived their weight had lower blood pressure in adulthood than those who perceived themselves to be overweight. The decrease in systolic blood pressure was −2.5 mmHg (95% CI:−4.3,−0.7; p=0.006). Although the interaction by gender was statistically insignificant (p=0.289), important differences appeared upon stratification by gender. Young men showed no significant difference in adult blood pressure related to weight self-perception. Conversely, in young women, weight under-perception was associated with an average decrease in systolic blood pressure of −4.3 mmHg (95% CI:−7.0,−1.7; p=0.002). Conclusions Contrary to conventional wisdom, weight under-perception is associated with improved health markers in young women. The observed differences in blood pressure are clinically relevant in magnitude, and interventions to correct weight under-perception should be re-examined for unintended consequences.

The Cardiometabolic Burden of Self-Perceived Obesity: A Multilevel Analysis of a Nationally Representative Sample of Korean Adults

“…Our results are consistent with the findings from recent studies showing that perception of normal weight (i.e., weight underperception) was associated with lower systolic blood pressure 13 and more favorable physiological functioning (i.e., a composite measure of inflammatory, cardiovascular, and metabolic biomarkers) 10 among US youth with overweight/obesity. While these studies found no difference in the association across gender 10 , 13 , we found a stronger association between weight perception and MetS among men than women. This is contrary to our initial hypothesis that perceived normal weight (vs. perceived obesity) would be more protective among women than men given that fat bias has been found to be more strongly directed toward women than men 24 , 25 .…”

“…Additionally, recent studies have found that being identified as overweight/obese by others (i.e., weight labeling) and by BMI report cards through BMI screening is associated with increased weight gain among US female youth 34 , 35 . By inter-relating weight stigma, identification of overweight/obese status by others or BMI report cards, and self-perception of being obese, recent studies have suggested that individuals who accurately perceive their overweight/obese status might experience negative psychological processes related with weight stigma and body dissatisfaction, which can result in weight gain and cardiometabolic dysregulations 8 – 10 , 13 , 27 .…”

“…Recent research, however, has revealed contradictory findings, whereby weight misperception (vs. accurate perception) among individuals with overweight/obesity led to more favorable outcomes in weight gain 9 – 11 , depressive symptoms 10 , 12 , and cardiometabolic functioning 10 , 13 . Furthermore, in a recent systematic review, Haynes and colleagues (2018) concluded that perception of obesity (vs. perception of normal weight) is associated with more unfavorable weight-related outcomes such as disordered eating, unhealthy weight control practice, and weight gain, regardless of the accuracy of the perception 14 .…”

“…However, gaps exist in the current understanding of the association between weight perception and cardiometabolic risks among Asian populations. For instance, despite the emerging evidence showing the harmful influences of accurate weight perception on cardiometabolic outcomes among individuals with obesity in Western countries 9 – 11 , 13 , previous Korean studies generally framed weight misperception as a cognitive bias that should be corrected regardless of weight status 21 – 23 .…”

Self‐perception of overweight and obesity: A review of mental and physical health outcomes

“…71 Another study drawing on the same US sample showed that adolescents with overweight and obesity who self-perceived as having overweight went on to experience raised blood pressure levels relative to those who self-perceived as normal weight. 72 Likewise, in a study of Korean adults, participants who self-identified as being overweight or obese showed a worse profile for biological markers of underlying metabolic health than participants who do not identify themselves as having overweight. 47 From these studies, it is not clear whether selfidentification of overweight acts on biological health indirectly through unhealthy lifestyle behaviours or via a more direct pathway involving a chronic biological stress response.…”