Introduction:
Social media create new opportunities and challenges for public health promotion. Users often come across with nutrition and body-related content uploaded by health and non-health professionals. The purpose of this study was to investigate the use of social media by Greek adolescents and young adults, and its impact on their dietary choices, emotions regarding food consumption and body image.

Material and Methods:
An online questionnaire assessing dietary choices and feelings around food was distributed to people aged 13-27 and was answered by 200 participants of both sexes. The collected data were analyzed using SPSS.

Results:
Social media were found to be the preferred nutrition information source for 80% of the participants, while Instagram, YouTube and Facebook were the most used platforms. Dietitians’ professional social media accounts were the most trusted source (76%). Overall, users’ dietary choices seemed to be moderately affected by social media (38%). In terms of their feelings about food consumption, participants stated that they find posts about healthy eating and new recipes inspiring (66%), and although images of delicious, yet less nutritious food, appeared to create the need for participants to consume such foods, yet 51% mentioned that eventually did not do it. A moderate level of emotional pressure from social media was observed in the sample regarding body image, while their stress seemed to be mainly related to obtaining a fitter body (32%) or a "perfect body" (31%) and to a lesser extent they were interested in losing weight (27%).

Conclusions:
Social media can be a useful tool for nutrition professionals aiming to educate young people on a healthy diet. The results also suggest that social media can influence not only their body image, like other types of media before, but also their emotions and eating behavior, with further research needed to confirm and understand this relationship.