As US health insurers ask customers to wear fitness trackers, are they opening a Pandora's Box of ethical dilemmas and business threats?

Ed Butler speaks to Brooks Tingle, chief executive of insurer John Hancock, which has been pioneering the controversial policy of rewarding customers willing to demonstrate that they exercise more. But Dr Michael Kurisu, director of the UCSD Center for Integrative Medicine in San Diego, asks what happens to those customers who refuse to participate? Plus the Financial Times' Undercover Economist, Tim Harford, talks us through the hazards and adversities of the insurance business, and why more information could obviate the purpose of insurance altogether.

(Picture: Young man checking his fitness tracker; Credit: kali9/Getty Images)