Purpose: To assess whether two indicators of social class, education and occupation, have independent and/or synergistic effects in determining the body mass and overweight.
Methods: Body mass index (BMI), education, and occupation were assessed in a survey of 1767 men and 1268 women from a representative sample of currently working people of the general population of Geneva, Switzerland. Education and occupation were categorized as low, medium, and high. Overweight was defined as BMI > or = 25 kg/m(2).
Results: The prevalence of overweight was 52.1% in men and 28.7% in women. Men with overweight were more likely to have low education while women with overweight had lower education and lower occupation. Education and occupation were inversely related to BMI in both genders and, in women, had a synergistic effect (p-value for the interaction = 0.03).
Conclusions: Education and occupation have independent and, in women, synergistic effects on BMI. The two indicators may express different mechanisms through which low social class is related to high body mass.