Gamification is a popular design approach with the purpose to increase engagement and continuous use of Health Behaviour Change Support Systems (HBCSS) with the purpose to establish health and wellbeing. It is widely employed for promoting healthier life choices or for supporting people with chronic diseases in their daily activities. Yet, there is a lack of evidence concerning gamification and its ability to sustain favourable effects on health behaviour change. This paper presents a scoping review about the long-term perspective in gamified HBCSS, focusing primarily on IT-reliant systems that treat individual lifestyle habits like healthy nutrition, exercise or smoking cessation. We systematically selected studies that consider gamified HBCSS for health promotion and discuss to what extent long-term engagement is explicitly included in their design. Our results underline a deficit of consideration of the long-term perspective as well as a lack of measurement related to the lasting effects of gamification. We therefore propose to intensify the use of longitudinal and prospective observational studies in the context of HBCSS, in order to increase the level of evidence of gamification interventions.