Attitudes, choices and expenditures on dietary supplements among adult members at low-cost gymnasiums in Johannesburg

Abstract

Dietary supplement use is on the increase globally with people seeking to achieve health and fitness goals through supplementation use. This caused gymnasiums to become a major market for dietary supplements. However, most dietary supplements have not been scientifically proven and there are reports of possible adverse effects associated with some dietary supplements. It is, therefore, of interest to research how well-informed dietary supplement users are. Numerous researchers have given insight into dietary supplement use among athletes and members of upmarket gymnasiums. However, not much is known about dietary supplement use in low-cost gymnasiums. A study was conducted to establish factors influencing dietary supplement use in low-cost gyms, the sources of information that dietary supplement users access and how much dietary supplement users spend monthly on supplements, were investigated. A mixed-method research design was followed at four selected low-cost gymnasiums in Johannesburg belonging to a popular fitness chain that classifies its gymnasium branches according to membership fee and services offered. Participants (n=351) were randomly selected from the four gyms. The initial stage of the study comprised of a self-administered validated quantitative survey on knowledge and attitudes regarding supplement use. In order to gain a deeper understanding of themes generated from results of the survey, eighteen participants from the survey were randomly selected to participate in three focus group discussions after which data saturation was reached. Two articles were submitted from this study. The first article focuses on the results from the quantitative survey. Overall prevalence of dietary supplement (DS) use was 53.4%. Among males 59% were users whereas 38.8% among females used DS. Dietary Supplement use was associated with gender (P<0.05). Men used body-building DS such as whey protein, creatine and BCAA to gain muscle (r=0.83; p<0.001). Women (r=0.4; p<0.013), preferred weight loss supplements such as Conjugated Linoleic Acid (CLA) and vitamins r=0.542; (p<0.000). DS expenditure (p<0.05, effect size r >0.5) was positively correlated to reasons for DS use; p<0.000 to gain muscle r=0.611, to improve performance r=0.681, to achieve personal goals r=0.702 and to maintain health r=0.522. Among non-users, more females than males felt DS were unnecessary (p=0.001), against their beliefs (p=0.000) and that they do not trust the DS companies (p=0.012) Whereas more males than females agreed they felt tempted to use performance enhancing substances (p=0.015). The main source of information for DS users were; 51% internet and 34% friends and fellow gym members. The least consulted were physicians (4%), scientific journals (4%) and biokineticists (3%). The second article focuses on perceptions of low-cost gym members and how these attitudes influence expenditure on DS. Dietary supplement users believe: DS are effective in achieving results faster, DS benefits outweigh the possible risks, DS are only risky to people with underlying health conditions, normal food is less nutritional because of genetic modification and that DS are cheaper as their nutritional value is measured and require no dietician. The study concluded that DS users in low-cost gymnasiums are not adequately informed about DS and, therefore, put their health at risk and the risk of a disproportionate financial burden of spending on products with little or no benefit. As such, the study recommends that despite their cost saving drive, low-cost gymnasiums make dietitians available or conduct awareness campaigns to educate members on DS.