As someone with experience as a mental health therapist, let me say that one sure way improve mental health is get rid of all the crap in the body, mind and life. Remove doubts from the mind. Remove insults to the body and mind. Don't let garbage and pollution overrun the body. Don't live in filth and squalor. Clean it out. Clean it out from the mind, body and environment and don't let come back in.
The reason why modern medicine improved health, why human life spans increased in modern times, is because of effective sanitation, proper hygeine and disinfective agents. Good health and sanity begin with sanitation.
A message for improving everyone's life and happiness.