According to a new study released by the National Institute of Environmental Health Sciences, the health benefits of switching from car driving to bicycling are substantially greater than the risks.
From the Abstract:
For the individuals who shift from car to bicycle, we estimated that beneficial effects of increased physical activity are substantially larger (3 – 14 months gained) than the potential mortality effect of increased inhaled air pollution doses (0.8 – 40 days lost) and the increase in traffic accidents (5 – 9 days lost). Societal benefits are even larger due to a modest reduction in air pollution and greenhouse gas emissions and traffic accidents.
Conclusions: On average, the estimated health benefits of cycling were substantially larger than the risks relative to car driving for individuals shifting mode of transport.