Aim: This study assessed the impact of a medical undergraduate course which contained nutrition content on medical students' self-perceived nutrition intake and self-efficacy to improve their health behaviours and counselling practices. Method: Two hundred and thirty nine medical students enrolled in a 12-week nutrition-related course at the University of Auckland were invited to complete an anonymous questionnaire before and after the course with their before and after course responses linked by student identification numbers. The questionnaires were adapted from a previous evaluation of a Preventive Medicine and Nutrition course and measured students' self-perceived nutrition intake and self-efficacy to improve their health behaviours and counselling practices. These responses were compared to a control group of 44 undergraduate biomedical science students. Results: Sixty one medical students completed both questionnaires (25.5%). At baseline, medical students described their eating habits differently from non-medical students (p=0.0261) and reported a higher level of physical activity to the control students (P= 0.0139). Post-course, medical students reported a higher frequency of wholegrain food intake (P=0.0229) and lower levels of physical activity than the controls (P=0.0342). Also post course, medical students felt less comfortable making nutrition recommendations to family or friends (P=0.008). Most medical students (63.9%) perceived that they were more aware of their own dietary choices, and some (15.3%) reported they were more likely to counsel patients on lifestyle behaviour. Conclusions: Students can increase awareness of their own nutrition behaviour after undertaking a course that includes nutrition in the initial phase of their medical degree. Further investigation of how medical students' confidence to provide nutrition advice evolves throughout their training and in future practice is required.