The risks you run : wWhat are the most serious threats to life expectancy in the United States? : a noted scientist gives some surprising answers.

It is possible statistically to project how long an average individual of a given age may be expected to live. It is also possible to calculate the average number of days or years of life that will be subtracted from this total by incurring a given risk -such as smoking cigarettes, over-eating, or becoming a human cannonball.