With the global obesity epidemic and concerns about the carbon footprint of automobile travel,  University of Wisconsin (Wisconsin, USA) researchers submit that more people should eliminate short auto trips and in lieu of bicycling. Moving five-mile round trips from cars to bikes is a win-win situation that is often ignored in discussions of transportation alternatives, but Jonathan Patz  and colleagues submit that doing so during the warmest six months of the year can save  $3.8 billion per year from avoided mortality and reduced health care costs for conditions including obesity and heart disease.  Writing that: “We estimate that the combined benefits of improved air quality and physical fitness would exceed $7 billion/year,” the researchers conclude that: “Our findings suggest that significant health and economic benefits are possible if bicycling replaces short car trips. Less auto dependence in urban areas would also improve health in downwind rural settings.”