Background: It has been suggested that the association between social disadvantage in childhood and adult mortality could come about through processes related to the family environment in which the child is raised. This study examines the relationship of fathers' social class with health behaviour in middle age and assesses the potential mediating role of cognitive function, educational status and social integration in young adulthood in these relationships.
Methods: We used data from the Metropolit cohort which includes 11 532 Danish men born in 1953 with information on fathers' social class at participants' birth and assessments of cognitive performance, education and social integration in early adulthood. In 2004, 6292 of these men participated in a follow-up survey on health and behaviour. Logistic regression was used to investigate the association of father's social class with smoking, alcohol drinking, leisure-time physical activity and the intake of fruit and vegetables in midlife.
Results: Middle-aged men with fathers from higher social classes were more often ex-smokers, wine drinkers and daily consumers of fruit or vegetables than men with working class fathers. Leisure activities and high alcohol consumption were not related to father's social class. Cognitive function and educational achievement at age 18 attenuated the association of father's social class with adult behaviour, while indicators of social integration had very little impact on the associations.
Conclusions: Father's social class influences adult smoking, alcohol preference and food intake, and a major part of the effect is mediated through cognitive function and education.