On NPR this morning, David Ropeik was supposed to talk about how

Americans worry excessively about terrorism and disease yet remain oblivious to more prevalent threats from environmental hazards and avoidable health risks, such as being overweight and physically inactive.

Instead, it sounded to me as if he thought we should be really alarmed about other stuff, like indoor pollution, medical errors, and food poisoning. The question is, what level should risk reach before one becomes alarmed?