Mental disorders are highly prevalent worldwide. Unfortunately, most people with these disorders do not receive any treatment. This is due in part to a large set of barriers (e.g., no access to therapists or clinics, lack of insurance, stigma) that impede seeking and obtaining mental health services. Many lifestyle interventions that are not part of traditional mental health services have indirect effects on reducing symptoms of mental disorders. These are interventions that target a direct focus (e.g., physical health, socialization, general well-being) but also have indirect and significant impact on reducing mental disorders. This article discusses indirect interventions as an additional way of reaching people in need of help with mental health problems. Interventions such as physical activity and exercise, diet, addressing sleep problems, yoga, tai chi, qigong, and volunteering have indirect beneficial effects. This article highlights the scope of mental illness as a background, introduces indirect interventions, and details three illustrations with evidence that targeting one focus with indirect effects on improving mental disorders. The interventions point to a category of interventions are not systematically used in the care of mental health problems. Among their many advantages is the prospect of their use at the levels of individuals and populations. Indirect interventions do not replace any of the current advances in treatment but add to ways of reaching people in need.