Aim Research suggests that people with mental illness frequently have worse physical health than the general population. Our study sought to investigate the health behaviours of mental health consumers in New Zealand, as we hoped that by clearly describing this group more targeted healthcare could be provided. Method We surveyed 404 adult mental health consumers about their: height and weight, fruit and vegetable intake, exercise activity, smoking, alcohol and drug use. Results We found that mental health consumers abstained from alcohol more often than those from the general population sample. However, we also found increased obesity, poorer eating habits, less physical activity, and a higher proportion of smokers among mental health consumers. We also found that those who did drink alcohol did so more heavily than drinkers from the general population sample. Finally, there were a number of interesting demographic variations among mental health consumers in terms of their health behaviours. For example, those in the European/Other ethnic group more often consumed an alcoholic drink at least 3 or 4 times a week than those in other ethnic groups, and those in the Pacific group did this less often. Conclusions Mental health consumers cannot be stereotyped as a single homogeneous group in relation to their health behaviours. Implications Health professionals should strongly encourage engagement from mental health populations to identify their physical health behaviours. Individual differences in health behaviours should not be ignored just because a mental illness is present.