There are areas known as 'Blue Zones' where people were thought to live very long lives. 

It was thought to have something to do with lifestyles in these spots, but one demographer has debunked the entire notion. 

Also, we discuss the best way to maintain weight loss in adolescents with weight-related health problems. 

How to screen for prostate cancer better, with fewer false alarms. And a new protocol that could reduce the toxicity of Hodgkin lymphoma treatment.