Television Watching is Positively Associated with Body Composition among Adults with High Genetic Predisposition to Obesity: Population‐based Study in South China

Abstract

ObjectiveGenetic predisposition and environmental factors (i.e. physical activity (PA), sedentary behavior (SB)) are important contributors to adulthood obesity. Previous studies on gene‐lifestyle interaction and obesity have focused mostly on the FTO gene and PA, whereas little attention has been paid to SB, particular in China. We examined whether the SB was associated with body composition measures among Chinese adults and whether these associations were modified by genetic predisposition.MethodsData on total time of SB, non‐screen based SB, screen‐based SB and specific types of screen‐based SB (television watching, computer/phone using), moderate‐to‐vigorous physical activity (MVPA) and dietary intake of 2423 Chinese adults (56.34% women) aged 25–65 years were obtained by validated questionnaires. Height and weight were measured to calculate body mass index (BMI), percent body fat (%BF), fat mass index (FMI) and fat‐free mass index (FFMI). Genetic risk scores (GRS weighted) were calculated on 9 loci confirmed to be associated with obesity in populations of Chinese. Multivariable linear generalized regression models were used to examine the association between SB, MVPA and body composition measures among adults with different genetic susceptibility.ResultsTime spent on television watching was positively associated with body composition measures among adults with a high obesity GRSweighted after adjustment for gender, age, family monthly income, occupation, smoking status, MVPA energy expenditure and total energy intake (p<0.03, n=1084). That is, for each hour increment in television watching was associated with approximately 0.19 kg/m2 higher BMI, 0.23% higher %BF, 0.12 kg/m2 higher FMI and 0.07 kg/m2 higher FFMI, respectively. Total time of SB, non‐screen based SB, screen‐based SB and computer/phone using was not related to any body composition measures among Chinese adults in the present analysis.ConclusionOur study indicates that television watching is of relevance for body composition among Chinese adults with high genetic predispositions to obesity.Support or Funding InformationAll phases of this study were supported by research grant from the National Nature Science Foundation of China (No. 81472976)