Abstract
This study used the latest waves of Add Health longitudinal data to assess the size of the protective effect of religiosity on later sexual behaviour in young adults (number of opposite sex partners and early sexual initiation). Related research questions were investigated, namely whether the influence of higher religiosity on sexual behaviour operates linearly and whether findings are robust to omitted variables bias. A general finding is that only for highly religious male and female participants is the effect robust. A related finding is that, after accounting for the protective effect of high religiosity, the independent effect of being religiously affiliated is protective for women of Catholic affiliation (compared to having no affiliation) but weakly towards more promiscuous behaviour for men of Catholic affiliation (gender difference statistically significant). This suggests that some religiously affiliated young males may see less of a need to reconcile any conflict between religious teachings and their sexual behaviour, unless religious teachings are internalized. Finally, after investigating the robustness of findings to biases due to omitted variables bias, there is additional support to the main conclusion that a robust effect of religiosity on sexual behaviour can be established only in individuals of high religiosity.