Despite elevated rates of suicide and evidence of poor mental health among medical professionals, there is a paucity of research in the UK into the mental health of students destined for these careers. This study estimated and compared the prevalence of mental ill-health in students studying veterinary medicine, medicine, dentistry and pharmacy in the United Kingdom. A group of law students was also included, who, although subject to similar stressors as undergraduates, do not go on to share a heightened risk of suicide as professionals. A total of 1744 respondents completed a questionnaire with validated measures to assess wellbeing, psychological distress, depression and suicidal ideation and attempts. Results indicated that law students experienced the poorest mental health of the student groups studied. Wellbeing was highest among veterinary and medical students. However, the medical students were the most likely to have previously attempted suicide. These findings highlight the importance of directly comparing student groups and of appropriately supporting students as they progress through training and into the professions.