Why do people use dietary supplements? Exploring the role of psychological and socio-cognitive factors

Abstract

Background: Worldwide, the use of dietary supplements is increasing. However, there is still no scientific consensus whether supplements are necessary to meet one’s daily nutritional needs. This study attempted to explore psychological and socio-cognitional motives for (non)usage, applying the Integrated Change Model as theoretical background. Method: In total 11 focus group discussions were held among users (n=28) and non-users (n=19) separately. A theory-based structured interview guide with open ended questions was used during each session. Interviews were audiotaped, then transcribed and analyzed following the principles of framework analysis. Findings: Some themes identified were: lack of confidence towards the nutritional knowledge of general practitioners and dieticians, skepticism towards the practices of food industry in general (e.g. sprayed fruits and vegetables) and the nutritional value of food. Additionally, many people had several misconceptions about how supplements are produced and controlled. Discussion: This study contributes to the understanding why people use dietary supplements. This information can be applied for setting up communication strategies adapted to the characteristics and needs of consumers.