Weighing cessation: Rising adiposity of current smokers in NHANES

Rising rates of obesity may have interacting effects with smoking given associated cardiovascular risks and cessation-associated weight gain. This study aimed to assess the change in body mass index (BMI) magnitude and prevalence of obesity and central adiposity over time among current smokers and to compare with that of former and never smokers to describe how the obesity and tobacco epidemics interrelate.

Using data from the National Health and Nutrition Examination Survey (NHANES) 1976-2018, survey-weighted, internally standardized analyses were used to look at outcomes of BMI, BMI category, and central adiposity by smoking status. A nonparametric test assessed trend over time.

The standardized proportion of current smokers with obesity increased from 11.6% in NHANES II to 36.3% in continuous NHANES 2017-2018; at the latest assessment this proportion was significantly lower than for former smokers. Mean BMI among current smokers also increased, from 24.7 kg/m2 to 28.5 kg/m2 among current smokers, which is significantly lower than among former smokers and never smokers at the latest time point. The standardized proportion of current smokers with central adiposity also increased, from 34.3% to 54.1%; again, at the latest time point the proportion was lower than for former smokers or never smokers.

Between 1976 and 2018, smoking rates decreased while adiposity increased among current, former, and never smokers. Over a third of current smokers meet BMI criteria for obesity and over half have an elevated waist circumference. It is imperative that weight management strategies be incorporated into smoking cessation approaches.