Background: Changes in lifestyles and in the environment over the last decades are probably the most important cause of the overweight epidemic, but the findings are inconsistent among studies. The purpose of this study was to investigate the association of several socio-economic and lifestyle factors with overweight in Flemish adults, using BMI > or = 25 kg/m2, waist circumference (WC) > or = 94 cm (men) or > or = 80 cm (women) and the combination of BMI and WC for identifying overweight.
Methods: This cross-sectional epidemiological study was conducted by the Flemish Policy Research Centre Sport, Physical Activity and Health between October 2002 and February 2004 in 46 Flemish communities. A total of 4903 Flemish adults (2595 men and 2308 women), aged 18 to 75 years, from a population-based random sample were included in the analysis. Body weight, height and WC were measured, and socio-economic and lifestyle factors were reported by means of validated questionnaires.
Results: The results of the logistic regressions revealed that age is positively associated with overweight in both genders. Alcohol consumption is associated with overweight only in men. Men smoking in the past and watching TV >11 h/week have significantly higher OR's for overweight, while men who participate in health related sports >4 h/week have significantly lower OR's for overweight. In women, watching TV >9 h/week was positively associated with overweight. Women who are current smokers or participate in health related sports >2.5 h/week or with a higher educational level have significantly lower odds for overweight. Different results are observed between the first (BMI) and the second model (WC) in both genders. In men, the models differ for education and health related sports, while in women they differ for smoking status and leisure time physical activity.
Conclusion: The present study confirms the contention that overweight is a multifactorial problem. Age and TV viewing are positively associated with overweight, while educational level and health related sports are negatively related to overweight in both genders. In men, alcohol consumption and smoking in the past are also among the lifestyle factors associated with overweight. This study also indicates that BMI and WC do not have the same discriminative function regarding different lifestyle factors.