Weight status misperception and its association with socio-demographic, lifestyle, and mental health-related factors among school adolescents in Malaysia: a nationwide cross-sectional study

Abstract Background Weight status misperception is an emerging public health concern among adolescents and may adversely affect their physical health, weight management behaviors, and psychosocial well-being. This study examined the prevalence of weight status misperception among school-going adolescents in Malaysia and identified socio-demographic, lifestyle, and mental health-related factors associated with weight status underestimation and overestimation. Methods Data were derived from the 2022 National Health and Morbidity Survey (NHMS): Adolescent Health Survey, a nationwide cross-sectional school-based survey. A total of 33,523 adolescents aged 13–17 years from 239 randomly selected secondary schools completed self-administered Global School-based Student Health Survey (GSHS) questionnaires and underwent anthropometric assessments. Actual weight status was classified using WHO body mass index (BMI)-for-age criteria and compared with self-perceived weight. Weighted Cohen’s kappa test assessed agreement between measured BMI and perceived weight status. Multinomial logistic regression analysis was performed to identify factors associated with weight status underestimation and overestimation. Results Overall, 47.9% of adolescents misperceived their own weight status, with 30.8% underestimated and 17.1% overestimated their weight status, while 52.1% had an accurate perception. Agreement between actual and perceived weight status was moderate (κ = 0.466, p < 0.001). Adolescents aged 13 years (aOR 2.10, 95% CI: 1.89–2.33), ever/current drug users (aOR 1.22, 95% CI: 1.07–1.39), and those who frequently consumed soft drinks (aOR 1.10, 95% CI: 1.02–1.18) and fast food (aOR 1.23, 95% CI: 1.11–1.37) were more likely to underestimate their weight. Overestimation was significantly associated with female gender (aOR 1.95, 95% CI: 1.75–2.16), inadequate fruit intake (aOR 1.16, 95% CI: 1.07–1.25), frequent fast food consumption (aOR 1.23, 95% CI: 1.08–1.40), loneliness (aOR 1.16, 95% CI: 1.02–1.32), depression (aOR 1.39, 95% CI: 1.23–1.57), and suicidal ideation (aOR 1.16, 95% CI: 1.03–1.32). Conclusion Nearly half of Malaysian adolescents misperceived their weight status. Weight status misperception was associated with a complex interplay of socio-demographic, lifestyle, and mental health factors, highlighting the need for integrated school-based interventions that promote accurate body weight perception, healthy lifestyle practices, and mental health support.