Dietary supplement usage during pregnancy and lactation: role of online social capital and health information-seeking behaviour

Purpose – The main objective of this study is to assess the applicability and robustness of the information motivation behavioural skills (IMB) model in determining dietary supplement usage of pregnant and breastfeeding women. More specifically, we examine the indirect effects of online social capital and internet use for health information on dietary supplement usage through self-efficacy and the moderating role of educational attainment. Design/methodology/approach – Data was collected from 415 pregnant and breastfeeding Italian women using a self-administered questionnaire. Hypotheses were tested using Hayes’s (2013) PROCESS macro for SPSS. Findings – Internet use for health information is directly associated with dietary supplement usage. Online social capital and internet use for health information positively influence dietary supplement usage through self-efficacy. However, the results from moderated mediation analyses show that the mediation effects are moderated by educational attainment so that indirect relationships were stronger among women with a lower level of education than among those with a higher level of education. Practical implications – Dietary supplement marketers and public health agencies can develop and implement dietary supplement promotional materials and interventions by disseminating information through the internet and social media and by strengthening social ties on online networking sites. Originality/value – The originality of this study lies in the use of the IMB model as a theoretical framework to examine the mediating role of self-efficacy and the moderating role of education in explaining the mechanism of how online social capital and internet use for health information influence dietary supplement usage. Keywords Online social capital, Internet use for health information, Self-efficacy, Dietary supplement usage, Pregnancy