Background: Food-related advertisements have been identified as influential factors affecting Australian adolescents' food preferences and dietary habits. Objective: This study aimed to investigate adolescents' (athletes and non-athletes) views about healthy eating, the advertising of discretionary foods and beverages, and the effects of food advertising on dietary behaviours. Method: Qualitative study involving the analysis of data from seven focus group discussions with young people aged 12-17 years (N = 27; 10 males and 17 females; 14 elite athletes, 13 non-athletes) from three different socioeconomic status secondary schools. Results: Both athlete and non-athlete participants discussed the importance of how social media is used for food advertisements. Many adolescents exhibited scepticism about the intent of advertising discretionary foods and beverages targeted toward adolescents. Three themes were identified from the data analysis: (1) physical and cognitive benefits of healthy eating; (2) scepticism, mistrust and ethical concerns about food and beverage advertisements targeted toward adolescents; and (3) portrayal of thin and fit ideals in social media. Conclusion: Health educators and policymakers addressing adolescent healthy eating behaviours should focus more fully on the influence of social media food advertising. Greater promotion of the importance of good nutrition during adolescence may optimise training performance and improve young people's nutritional knowledge and healthy eating habits.