Determinants of Dietary Supplements consumption in Healthy Adults: A Review of Existing Evidence (1996-2020)

Introduction Due to the high consumption of dietary supplements and the need to identify the factors affecting consumption to design effective interventions, the aim of the present review is to the factors affecting the consumption of supplements in studies conducted on healthy adults between 1996 and 2020. Materials and Methods The present study was conducted by reviewing 584 articles from the last 24 years and searching the databases of Scopus, PubMed, Science Direct Springer, Cochrane, Embase, Medlib, Magiran, SID, and the Google Scholar search engine. Based on the PRISMA guide, 54 articles were selected and reviewed. Results Most cross-sectional and cohort studies have shown the effect of gender, education, and age on dietary supplement consumption. The only trial study showed the effect of gender and only a review study showed the effect of gender, age, education, and income. Women take supplements more than men. With increasing education, age, physical activity, body mass, and income dietary supplements consumption increases. Other factors such as smoking, race and ethnicity, chronic diseases, alcohol consumption, living in a metropolitan, marriage, lifestyle, perceived health, and higher health awareness, drug use, and self-efficacy have also affected consumption. Conclusion The studies have been limited to examining the relationship between demographic factors and use and less attention has been paid to factors such as awareness and beliefs about supplement use. Therefore, in order to achieve more definitive results and increase the efficiency of interventions designed in the field of consumption of these supplements, it seems necessary to conduct prospective and intervention studies