ABSTRACT There is a compelling need to improve all physicians’ knowledge on lifestyle medicine (LM). This training needs to start early during medical education. This case report describes the feasibility and effects of integrating LM into an existing core curriculum of a Swedish undergraduate medical programme. A curriculum development project was organized using a six-step model: general needs assessment, targeted needs assessment, goals and objectives, educational strategies, implementation, and evaluation. New learning objectives regarding health, prevention and lifestyle medicine were formulated throughout the five-and-a-half-year programme. Learning activities and examinations were integrated in all courses with a structured progression and with focus on preventive activities in the workplace learning. The project was evaluated using student surveys of curricular quality, teacher survey of curricular content and integration in 2020, and an external review of adherence to the national qualitative target on preventive medicine. The project was executed during 2017–2018. Course evaluations and exit poll at graduation showed an overall high-quality student rating of education in prevention and in lifestyle counselling: on average, a score of 4.1/5 and 4.1/6, respectively. The teacher survey showed that over 70% of courses had a lasting increase in LM curricular content and that this content was to a large extent integrated into the existing course material. The external review concluded that the topic was well covered and integrated into the curriculum. LM could be successfully integrated into an existing medical programme curriculum with positive effects on student learning.