Researchers have concluded a six-month public smoking ban saw heart attack rates plummet by 60% in an American midwestern town. The strict ban imposed in Helena, Montana, outlawed smoking in public places from June 5 last year. It was suspended six months later following a legal challenge. But while the ban was in force, researchers used the opportunity to investigate the effect of such policies on public health. The study focused on St Peter's Community Hospital, which serves almost all heart patients in the community of 66,000 people. Researchers compared the number of heart attack patients admitted from the Helena...