Introduction:
During the last decades Dietary Supplements (DS) use has increased globally. It has often been associated with demographic factors, such as the Level of Education (LE) and Physical Activity (PA). However, information on Greek consumers is limited.

Objective:
The aim of this study was to investigate the Greek consumer attitudes towards the DS use, in relevance to the LE and PA. Specifically, the frequency and reasons for use/non-use of DS, types of DS, consumers’ knowledge, opinions, and behaviors towards DS were examined.

Methods:
Data collection was performed through an in-person questionnaire completion from 31,823 Greek consumers. Data digitization and transportation were performed by Microsoft Excel. The statistical analysis (Pearson’s Chi-Square test, Z-test, Correlation Analysis) was performed using SPSS.

Results:
History of DS use reached 56.4% and it was more prevalent among exercisers (61.2% vs 50.2%, p<0.05), and positively related to the LE (37.4-64.2%, p<0.05). The “good physical condition”, as a non-usage reason, and the “improvement of physical condition”, as a usage reason, were more frequently selected by exercisers and higher LE. However, the “fear of side-effects”, as a non-usage reason, and the “treatment of disease”, as a usage reason, were more frequently selected by non-exercisers and lower LE. Exercisers and higher LE agreed more frequently that “DS are generally safe”, and also considered more frequently the recommended daily allowance. However, only half of the respondents declared awareness of the DS overuse dangers.

Conclusions:
Exercisers and higher educated consumers, consider DS use as “supportive” of their healthy lifestyle, while non-exercisers and consumers with a lower LE as “therapeutical”. Nonetheless, there seems to be fertile ground for guidance of consumers, regardless of PA and LE, from healthcare professionals to prevent DS’ imprudent use.