The effect of body mass index on self-rated health in middle-aged and older adults: evidence from the China health and retirement longitudinal study

Background and aimsHealth promotion for middle-aged and older people has received a lot of attention recently in the context of healthy aging. Furthermore, it is unclear how body mass index (BMI) presently affects self-rated health (SRH), a reliable and representative indicator of health.MethodsThis study used longitudinal follow-up data from the China Health and Retirement Longitudinal Study (CHARLS). Systematic collection of information on the socio-demographic, lifestyle, and health status of the subjects. Binary logistic regression was used to investigate the relationship between BMI and SRH, and gender-specific variations were examined. Subgroup analysis was used to examine interactions, and the results of the research stability were demonstrated.ResultsAfter adjusting for age, gender, education level, marital status, place of residence, number of chronic diseases, alcohol consumption, smoking, depressive symptoms, and SRH at baseline, it was found that obesity grade 1 and obesity grade 2 were good contributors to SRH compared to normal weight individuals, and this association was different in males and females. According to the results of the subgroup analyses, those under 65 years old, with junior high school or less education, with a spouse, residing in a city, having one chronic disease, and not smoking or drinking, respectively, all had stable positive associations between obesity and SRH.ConclusionsOur findings suggest that obesity may be associated with good SRH. Teams of healthcare professionals should revisit the potential impact of obesity among middle-aged and older adults and focus on developing prevention strategies for morbid obesity.