Young adults entering the workforce are at increased risk of becoming overweight or obese. Yet, internationally, young adults are rarely targeted in health campaigns, and little is known on how to improve their interest and participation in health promotion efforts. Through 33 semi-structured interviews with young adults working in Singapore, we explored their engagement with existing public and workplace health promotion efforts that encouraged healthy eating and increased physical activity, and their subjective health in the context of their daily lives. Interviews were coded and thematically analysed, taking an inductive and deductive approach. Despite some interest in health messaging, participating working young adults rarely adopted health-promoting activities such as meeting daily recommended servings of fruits and vegetables and exercising regularly. Participants reported that the health promotion campaigns they were aware of, suggested actions that they couldn't incorporate in their lives as they did not address the barriers that they are facing from socio-environmental contributors such as long working hours, personal and social commitments, and the food environment. Furthermore, some considered their health to be good enough and therefore had little reason to change existing practices. Affordable and accessible health screenings were an objective way for young adults to re-evaluate their perceptions of their own health which motivated some to favourably change their behaviours. Our findings suggest that future health promotion campaigns would benefit from more fully addressing some of the existing barriers that young working adults face, in tandem with policy changes to directly tackle the socio-environmental conditions for young workers.