Fish oil users of Greece: Predictors, knowledge and habits regarding dietary supplement use

Background

Fish oil (FO) dietary supplements (DS) have gained popularity over the past few decades and emerged as one of the most popular DS in both Europe and the USA. However, in Greece, no study has been carried out to determine the prevalence and characteristics of FO consumers.

Objective

The aim of this study was to describe the stance (i.e., beliefs, knowledge and habits) and practices of FO users in Greece towards DS.

Methods

A cross-sectional study, using in-person questionnaires and a stratified random sampling technique, was conducted throughout 2018-2019. A total of 28491 Greek citizens over 15 years old were interviewed in 74 regional units corresponding to the 13 administrative regions of Greece. Having used DS at least once, deemed one as: DS+FO, if FO were among them; DS-FO, if FO were never used or DS non-user, if DS were never used. Pearson's chi-square test was used to determine independence between relevant outcome variables and FO use and multinomial logistic regression was performed to create models predictive of FO use.

Results

The sample consisted of 3.5% DS+FO, 51.3% DS-FO and 43.8% DS non-users, while 1.4% could not remember whether they had used DS. Significant predictors for being a DS+FO were identified. DS+FO were more likely to judge a DS-less diet as insufficient, support DS use and comprehend DS's labels. Also, DS+FO had used additional DS, considered more parameters when buying DS and were receivers of DS recommendations from more sources compared to DS-FO. 90% of DS users seek at least one approval source of their DS and 50% support DS recommendation by doctors.

Conclusion

Favorableness towards DS is more prevalent among DS+FO. Most respondents lack knowledge about the legislative background of DS and many would agree to professional guidance.

Prevalence, Determinants, and Consumer Stance towards Dietary Supplements According to Sex in a Large Greek Sample: A Cross-Sectional Study

A stratified random sampling technique was used in order to explore the prevalence of and the factors influencing dietary supplement (DS) use and the consumer stance towards DS by Greeks (n = 28,491, ≥15 years) according to sex. Additionally, we performed a Pearson’s chi-square to test within DS users for the dependence between sex and the examined factors, and binary logistic regression to create predictive DS user profiles. A history of DS use accounted for 55.5% and was more prevalent in women (58.4% vs. 52.3%, p < 0.001); multivitamins were the most popular DS used. The significant predictors for DS use for both sexes were age, education, employment status, exercise, and following a special diet, while BMI and monthly income were significant for women and men, respectively. The women and men DS users had mostly illness-health and fitness-related goals, respectively. Substantial proportions of the respondents had false beliefs about DS. A noticeable percentage of DS users displayed imprudent behavior regarding DS use, e.g., one out of five did not know the definition or did not take into consideration the recommended daily allowance. While several factors seemed to impact DS use, with certain differences between the sexes, the considerable lack of knowledgeable and responsible use of DS, with few differences between the sexes, observed can point state authorities and health professionals towards appropriate countermeasures.