Why we're so sleepy

"CBS This Morning" contributor Lee Woodruff reports on the latest trends in wearable fitness technology.

A new study finds that women taking 1,000 milligrams of calcium a day have a lower risk of dying, contradicting previous studied linking calcium to an increased risk of heart attacks. Dr. Holly Phillips explains.

CBS News contributor Dr. David Agus, director of the Westside Cancer Center at the University of Southern California, talks to the "CBS This Morning" co-hosts about why the cost for a genetic test for breast cancer is so high.

CBS News' Ben Tracy reports on an inventor whose idea for an artificial limb design was borne out of his own experience losing his lower leg in a sporting accident.

Despite new government labels on sunscreen due out this summer, one watchdog group says high SPF ratings can give people a false sense of security. Norah O'Donnell reports.

Dr. Allen Frances, co-author of the previous version of the "Diagnostic and Strategic Manual of Mental Disorders" -- known as "the psychiatrist's bible" -- discusses new, controversial changes to the text. Frances is the author of a new book called "Saving Normal."